| isolation and characterization of an arabidopsis thaliana c-8,7 sterol isomerase: functional and structural similarities to mammalian c-8,7 sterol isomerase/emopamil-binding protein. | the yeast c-8,7 sterol isomerase contains a polyvalent high-affinity drug binding site similar to mammalian sigma receptors. exogenously supplied sigma ligands inhibit sterol biosynthesis in yeast, demonstrating a pharmacological relationship between sigma ligand-binding and c-8,7 sterol isomerase activity. we report the isolation of an arabidopsis thaliana c-8,7 sterol isomerase by functional complementation of the corresponding sterol mutant in yeast and its characterization by exposure to sig ... | 1998 | 9862498 |
| arabidopsis cdna encoding a membrane-associated protein with an acyl-coa binding domain. | acyl-coa binding proteins (acbps) are small (ca. 10 kda) highly-conserved cytosolic proteins that bind long-chain acyl-coas. a novel cdna encoding acbp1, a predicted membrane protein of 24.1 kda with an acyl-coa binding protein domain at its carboxy terminus, was cloned from arabidopsis thaliana. at this domain, acbp1 showed 47% amino acid identity to brassica acbp and 35% to 40% amino acid identity to yeast, drosophila, bovine and human acbps. recombinant (his)6-acbp1 fusion protein was express ... | 1998 | 9862500 |
| fusions between green fluorescent protein and beta-glucuronidase as sensitive and vital bifunctional reporters in plants. | by fusing the genes encoding green fluorescent protein (gfp) and beta-glucuronidase (gus) we have created a set of bifunctional reporter constructs which are optimized for use in transient and stable expression studies in plants. this approach makes it possible to combine the advantage of gus, its high sensitivity in histochemical staining, with the advantages of gfp as a vital marker. the fusion proteins were functional in transient expression studies in tobacco using either dna bombardment or ... | 1998 | 9862502 |
| molecular cloning in arabidopsis thaliana of a new protein phosphatase 2c (pp2c) with homology to abi1 and abi2. | we report the cloning of both the cdna and the corresponding genomic sequence of a new pp2c from arabidopsis thaliana, named atp2c-ha (for homology to abi1/abi2). the atp2c-ha cdna contains an open reading frame of 1536 bp and encodes a putative protein of 511 amino acids with a predicted molecular mass of 55.7 kda. the atp2c-ha protein is composed of two domains, a c-terminal pp2c catalytic domain and a n-terminal extension of ca. 180 amino acid residues. the deduced amino acid sequence is 55% ... | 1998 | 9862504 |
| rav1, a novel dna-binding protein, binds to bipartite recognition sequence through two distinct dna-binding domains uniquely found in higher plants. | we have cloned and characterized two novel dna binding proteins designated rav1 and rav2 from arabidopsis thaliana. rav1 and rav2 contain two distinct amino acid sequence domains found only in higher plant species. the n-terminal regions of rav1 and rav2 are homologous to the ap2 dna-binding domain present in a family of transcription factors represented by the arabidopsis apetala2 and tobacco erebp proteins, while the c-terminal region exhibits homology to the highly conserved c-terminal domain ... | 1999 | 9862967 |
| psa causes oncogenic suppression of agrobacterium by inhibiting vire2 protein export. | when coresident with the ti (tumor-inducing) plasmid, the 21-kda product of the osa gene of the plasmid psa can suppress crown gall tumorigenesis incited by agrobacterium tumefaciens. neither t-dna processing nor vir (virulence) gene induction is affected by the presence of osa in the bacterium. we used arabidopsis thaliana root segments and tobacco leaf discs to demonstrate that osa inhibits a. tumefaciens from transforming these plants to the stable phenotypes of tumorigenesis, kanamycin resis ... | 1999 | 9864329 |
| regulation of serine biosynthesis in arabidopsis. crucial role of plastidic 3-phosphoglycerate dehydrogenase in non-photosynthetic tissues. | in plants, ser is synthesized through a couple of pathways. 3-phosphoglycerate dehydrogenase (pgdh), the first enzyme that is involved in the phosphorylated pathway of ser biosynthesis, is responsible for the oxidation of 3-phosphoglycerate to phosphohydroxypyruvate. here we report the first molecular cloning and characterization of pgdh from arabidopsis thaliana. sequence analysis of cdna and a genomic clone revealed that the pgdh gene is composed of three exons, encoding a 623-amino acid polyp ... | 1999 | 9867856 |
| the ecs1 gene of arabidopsis encodes a plant cell wall-associated protein and is potentially linked to a locus influencing resistance to xanthomonas campestris. | the interaction between arabidopsis and xanthomonas campestris pv. campestris (xcc) provides a useful model system to identify components that are involved in incompatible interactions of this phytopathogen and cruciferous plants. we have previously described a new gene from arabidopsis thaliana, ecs1 (formerly cxc750), which showed an ecotype-specific expression pattern, although homologous sequences are present in the genomes of all ecotypes tested. interestingly, ecs1 mrna transcripts were on ... | 1998 | 9869403 |
| expression of an anther-specific chalcone synthase-like gene is correlated with uninucleate microspore development in nicotiana sylvestris. | two cdna clones, specifically expressed in nicotiana sylvestris anthers during uninucleate microspore development, were isolated using a subtractive hybridization approach. sequence analysis showed that one of them, nschslk, displayed a high level of similarity to several anther-specific chalcone synthase-like (chslk) proteins and an orf from chromosome i of arabidopsis thaliana. a lower, but significant, similarity to chalcone synthases and closely related enzymes (chsre) was also detected. the ... | 1998 | 9869422 |
| phosphate transporter gene family of arabidopsis thaliana. | using a high-affinity phosphate transporter gene of arabidopsis thaliana, pht1, as a probe, three arabidopsis homologs were isolated, named pht4, pht5 and pht6, in addition to the previously isolated pht2 and pht3. the amino acid sequences deduced from the three nucleotides were 32-42% homologous with microbial phosphate transporters of saccharomyces cerevisiae (pho84), neurospora crassa (pho-5) and glomus versiforme (gvpt). pht1, pht2, pht3 and pht6 were clustered in a 25-kbp region of chromoso ... | 1998 | 9872450 |
| isolation of a cdna from arabidopsis thaliana that complements the sec14 mutant of yeast. | the sec14 gene of saccharomyces cerevisiae codes for a phosphatidylinositol-transfer protein (sec14p(sc)) which is capable of transferring both phosphatidylinositol and phosphatidylcholine between membranes in vitro. genetic and biochemical studies conducted in s. cerevisiae have shown that this protein acts as an inhibitor of phosphatidylcholine biosynthesis via the so-called kennedy pathway only. this inhibition is controlled by the binding of phospholipids to the sec14p(sc) protein. here we d ... | 1998 | 9874205 |
| reactivity studies of the tyrosyl radical in ribonucleotide reductase from mycobacterium tuberculosis and arabidopsis thaliana--comparison with escherichia coli and mouse. | ribonucleotide reductase (rnr) is a key enzyme for dna synthesis since it provides cells with deoxyribonucleotides, the dna precursors. class i alpha2beta2 rnrs contain a dinuclear iron center and an essential tyrosyl radical in the beta2 component (protein r2). this is also true for the purified protein r2 of mycobacterium tuberculosis rnr, as shown by iron analysis, light absorption and epr spectroscopy. epr spectroscopy at 286 ghz revealed a high g(x) value, suggesting that the radical is not ... | 1998 | 9874215 |
| purification and properties of the chloroplastic form of biotin holocarboxylase synthetase from arabidopsis thaliana overexpressed in escherichia coli. | holocarboxylase synthetases (hcss) are key enzymes in biotin utilisation in both prokaryotes and eukaryotes. in a previous study, we demonstrated that, in plants, hcs activity is localised in cytosol, chloroplasts and mitochondria. we also described the cloning and sequencing of a full-length cdna encoding an arabidopsis thaliana hcs isoform with a putative organelle-transit peptide. in the study reported here, this cdna was used to construct an overproducing escherichia coli strain. the recombi ... | 1998 | 9874227 |
| diversity and molecular evolution of the rps2 resistance gene in arabidopsis thaliana. | the rps2 gene in arabidopsis thaliana governs resistance to strains of the bacterial pathogen, pseudomonas syringae pv. tomato, that express the avrrpt2 gene. the two loci are involved in a gene-for-gene interaction. seventeen accessions of a. thaliana were sequenced to explore the diversity present in the coding region of the rps2 locus. an unusually high level of nucleotide polymorphisms was found (1.26%), with nearly half of the observed polymorphisms resulting in amino acid changes in the rp ... | 1999 | 9874813 |
| proteins involved in membrane transport between the er and the golgi apparatus: 21 putative plant homologues revealed by dbest searching. | numerous proteins have been identified in yeast and mammalian cells which are involved in trafficking between the endoplasmic reticulum and the golgi apparatus. a great number of partial cdna sequences now available from the two major plant model species, arabidopsis thaliana and oryza sativa, makes it possible to identify putative plant homologues of known genes/proteins from non-plant species. the authors used this approach to screen the database of expressed sequence tags (dbest) in order to ... | 1998 | 9878102 |
| isolation of atmekk1 (a map kinase kinase kinase)-interacting proteins and analysis of a map kinase cascade in arabidopsis. | in plants, a number of map kinase (mapk), mapk kinase (mapkk), and mapkk kinase (mapkkk) homologues have been reported. however, there have been no reports of protein-protein interactions between these kinases or molecular analysis of mapk cascades in higher plants. to analyze a possible mapk cascade in arabidopsis thaliana, we took two molecular approaches. one is the two-hybrid screening of atmekk1 (a mapkkk)-interacting proteins; the other is an analysis of physical and functional interaction ... | 1998 | 9878570 |
| reciprocal regulation of distinct asparagine synthetase genes by light and metabolites in arabidopsis thaliana. | in plants, the amino acid asparagine serves as an important nitrogen transport compound whose levels are dramatically regulated by light in many plant species, including arabidopsis thaliana. to elucidate the mechanisms regulating the flux of assimilated nitrogen into asparagine, we examined the regulation of the gene family for asparagine synthetase in arabidopsis. in addition to the previously identified asn1 gene, we identified a novel class of asparagine synthetase genes in arabidopsis (asn2 ... | 1998 | 9881155 |
| a gfp-mouse talin fusion protein labels plant actin filaments in vivo and visualizes the actin cytoskeleton in growing pollen tubes. | the c-terminus of mouse talin (amino acids 2345-2541) is responsible for all of the protein's f-actin binding capacity. unlike full-length talin, the c-terminal f-actin binding domain is unable to nucleate actin polymerization. we have found that transient and stable expression of the talin actin-binding domain fused to the c-terminus of the green fluorescent protein (gfp-mtn) can visualize the actin cytoskeleton in different types of living plant cells without affecting cell morphology or funct ... | 1998 | 9881160 |
| molecular characterization of plastidic phosphoserine aminotransferase in serine biosynthesis from arabidopsis. | serine biosynthesis in plants proceeds by two pathways; a photorespiratory pathway which is associated with photorespiration and a pathway from phosphoglycerate. a cdna encoding plastidic phosphoserine aminotransferase (psat) which catalyzes the formation of phosphoserine from phosphohydroxypyruvate has been isolated from arabidopsis thaliana. genomic dna blot analysis indicated that this enzyme is most probably encoded by a single gene and is mapped on the lower arm of chromosome 4. the deduced ... | 1998 | 9881164 |
| correlation of defense gene induction defects with powdery mildew susceptibility in arabidopsis enhanced disease susceptibility mutants. | we investigated the relative importance of specific arabidopsis thaliana genes in conferring resistance to bacterial versus fungal pathogens. we first developed a pathosystem involving the infection of arabidopsis accession columbia with a virulent isolate of the obligate biotrophic fungal pathogen erysiphe orontii. e. orontii elicited the accumulation of mrnas corresponding to the defense-related genes pr1, bgl2 (pr2), pr5 and gst1, but did not elicit production of the phytoalexin camalexin or ... | 1998 | 9881167 |
| cloning and characterization of the arabidopsis thaliana lupeol synthase gene. | a 2274 bp arabidopsis thaliana cdna was isolated that encodes a protein 57% identical to cycloartenol synthase from the same organism. the expressed recombinant protein encodes lupeol synthase, which converts oxidosqualene to the triterpene lupeol as the major product. lupeol synthase is a multifunctional enzyme that forms other triterpene alcohols, including beta-amyrin, as minor products. sequence analysis suggests that lupeol synthase diverged from cycloartenol synthase after plants diverged ... | 1998 | 9883589 |
| camalexin accumulation in arabis lyrata. | inoculation of leaves of arabis lyrata with either a bacterial pathogen pseudomonas syringae pv. maculicola strain es4326 or cochliobolus carbonum, a fungal nonpathogen of a. lyrata, resulted in the accumulation of a compound with similar chromatographic and fluorescent properties to that of camalexin (i), a phytoalexin produced by arabidopsis thaliana. a. lyrata is closely related to a. thaliana. high resolution electron impact mass spectroscopic and proton nmr analysis confirmed that the compo ... | 1998 | 9887527 |
| involvement of arabidopsis thaliana ribosomal protein s27 in mrna degradation triggered by genotoxic stress. | a recessive arabidopsis mutant with elevated sensitivity to dna damaging treatments was identified in one out of 800 families generated by t-dna insertion mutagenesis. the t-dna generated a chromosomal deletion of 1287 bp in the promoter of one of three s27 ribosomal protein genes (ars27a) preventing its expression. seedlings of ars27a developed normally under standard growth conditions, suggesting wild-type proficiency of translation. however, growth was strongly inhibited in media supplemented ... | 1999 | 9889204 |
| characterization of a calcium-dependent protein kinase of tobacco leaves that is associated with the plasma membrane and is inducible by sucrose. | the plasma membrane fraction from leaves of tobacco contains a 54-kda protein with autophosphorylation activity, and the level of this protein increases after feeding of leaves with sucrose [ohto and nakamura (1995) plant physiol. 109: 973]. the 54-kda autophosphorylation protein could not be released from the plasma membrane by treatment with salt or alkali but could be efficiently solubilized by 1% sodium deoxycholate (nadoc). ion-exchange chromatography of the nadoc-solubilized proteins in th ... | 1998 | 9891416 |
| selectable viruses and altered susceptibility mutants in arabidopsis thaliana. | the genetic basis for susceptibility or nonsusceptibility of plants to viruses is understood poorly. two selectable tobacco etch virus (tev) strains were developed for identification of arabidopsis thaliana mutants with either gain-of-susceptibility or loss-of-susceptibility phenotypes. these strains conferred a conditional-survival phenotype to arabidopsis based on systemic expression of herbicide resistance or proherbicide sensitivity genes, thereby facilitating mass selections and screens for ... | 1999 | 9892709 |
| heterologous myb genes distinct from gl1 enhance trichome production when overexpressed in nicotiana tabacum. | myb-class transcription factors implicated in cell shape regulation were overexpressed in arabidopsis thaliana and nicotiana tabacum in an attempt to assess the extent to which cellular differentiation programs might be shared between these distantly related plants. glabrous 1, a myb gene required for trichome development in arabidopsis, did not alter the trichome phenotype of the tobacco plants in which it was overexpressed. mixta, which in antirrhinum majus is reported to regulate certain aspe ... | 1999 | 9895315 |
| two arabidopsis thaliana carotene desaturases, phytoene desaturase and zeta-carotene desaturase, expressed in escherichia coli, catalyze a poly-cis pathway to yield pro-lycopene. | we have expressed in escerichia coli the enzymes geranylgeranyl diphosphate synthase and phytoene synthase, from the soil bacterium erwinia stewartii, and the two carotene desaturases phytoene desaturase and carotene zeta-carotene desaturase from arabidopsis thaliana. we show that pro-lycopene (7,9,7',9'-tetra-cis)-lycopene is the main end product of the plant desaturation pathway in these cells. in addition, light is required in this system. whereas in the dark mainly zeta-carotene, the phytoen ... | 1999 | 9914519 |
| the yeast saccharomyces cerevisiae ydl112w orf encodes the putative 2'-o-ribose methyltransferase catalyzing the formation of gm18 in trnas. | the protein sequences of three known rna 2'-o-ribose methylases were used as probes for detecting putative homologs through iterative searches of genomic databases. we have identified 45 new positive open reading frames (orfs), mostly in prokaryotic genomes. five complete eukaryotic orfs were also detected, among which was a single orf (ydl112w) in the yeast saccharomyces cerevisiae genome. after genetic depletion of ydl112w, we observed a specific defect in trna ribose methylation, with the com ... | 1999 | 9917067 |
| classification of arabidopsis thaliana gene sequences: clustering of coding sequences into two groups according to codon usage improves gene prediction. | while genomic sequences are accumulating, finding the location of the genes remains a major issue that can be solved only for about a half of them by homology searches. prediction methods are thus required, but unfortunately are not fully satisfying. most prediction methods implicitly assume a unique model for genes. this is an oversimplification as demonstrated by the possibility to group coding sequences into several classes in escherichia coli and other genomes. as no classification existed f ... | 1999 | 9925779 |
| expression of the cell cycle in sperm of arabidopsis: implications for understanding patterns of gametogenesis and fertilization in plants and other eukaryotes. | the relationship between developmental events and the cell cycle was examined in sperm of arabidopsis thaliana. sperm of arabidopsis rapidly enter the s (synthesis) phase of the cell cycle after inception from mitosis of the generative cell. sperm in pollen grains within anthers continue to synthesize dna, and at the time of pollination, contain approximately 1.5c dna. following pollination, sperm continue through the s phase of the cell cycle during pollen tube growth. by the time pollen tubes ... | 1999 | 9927606 |
| expression cloning of ldlb, a gene essential for normal golgi function and assembly of the ldlcp complex. | the chinese hamster ovary (cho) cell mutants ldlc and ldlb, which exhibit almost identical phenotypes, define two genes required for multiple steps in the normal medial and trans golgi-associated processing of glycoconjugates. the ldlc gene encodes ldlcp, an approximately 80-kda protein, which in wild-type, but not ldlb, cells associates reversibly with the cytoplasmic surface of the golgi apparatus. here, we have used a retrovirus-based expression cloning system to clone a murine cdna, ldlb, th ... | 1999 | 9927668 |
| molecular characterisation of plant cdnas bnmap4kalpha1 and bnmap4kalpha2 belonging to the gck/sps1 subfamily of map kinase kinase kinase kinase. | several yeast and mammal map kinase modules require, upstream of their map kinase kinase kinase (map3k), a map3k kinase (map4k). an arabidopsis thaliana est clone, sharing identity to map4ks from yeast and mammals, has been used to isolate cdna clones from a brassica napus microspore-derived embryo cdna library. the bnmap4kalpha1 and bnmap4k-alpha2 clones encode putative proteins possessing the 12 subdomains of the serine/threonine protein kinase catalytic domain. a detailed analysis showed that ... | 1999 | 9931402 |
| establishment of framework p1 clones for map-based cloning and genome sequencing: direct rflp mapping of large clones. | large insert capacity, clone stability and convenient propagation in escherichia coli have made bacterial artificial chromosome and phage p1 vector-based libraries the first choice for large-scale sequencing projects, and these libraries have also proven useful for chromosome walking. the application of these libraries for either purpose is greatly facilitated by the establishment of a set of framework clones distributed across the genome. using a p1-based library of arabidopsis thaliana with ge ... | 1998 | 9931419 |
| expression cloning in fe2+ transport defective yeast of a novel maize myc transcription factor. | a complementation approach of the yeast fet3fet4 mutant strain, defective in both low- and high-affinity iron transport, was initiated as an attempt to characterize the fe(iii)-mugineic acid (ma) transporter from grasses. a maize cdna encoding a novel myc transcription factor, named 7e, was cloned by screening an iron-deficient maize root cdna expression library on a minimum media containing fe(iii)-deoxyma as a unique iron source. 7e expression restored growth specifically to the fet3 fet4 muta ... | 1998 | 9931428 |
| human and mouse homologs of the schizosaccharomyces pombe rad17+ cell cycle checkpoint control gene. | the schizosaccharomyces pombe rad17+ cell cycle checkpoint control gene is required for s-phase and g2/m arrest in response to both dna damage and incomplete dna replication. we isolated and characterized the putative human (rad17sp) and mouse (mrad17sp) homologs of the s. pombe rad17 (rad17sp) protein. the human rad17sp open reading frame (orf) encodes a protein of 681 amino acids; the mrad17sp orf codes for a protein of 688 amino acids. the mrad17sp messenger is highly expressed in the testis ... | 1999 | 9933569 |
| clp protease complexes and their diversity in chloroplasts. | the clp proteases represent a large, ancient atp-dependent protease family which in higher plants is known to be located in chloroplasts. the soluble, presumably multisubunit, enzyme of the organelle stroma is of dual genetic origin. it consists of a nuclear-encoded, regulatory subunit clpc, which is an atpase, and a plastid-encoded proteolytic subunit clpp, which is a serine protease. an additional, nuclear-encoded proteolytic subunit resembling clpp has been recently reported from tomato (scha ... | 1998 | 9951729 |
| the msg1 and axr1 genes of arabidopsis are likely to act independently in growth-curvature responses of hypocotyls. | growth-curvature responses of hypocotyls of arabidopsis thaliana (l.) heynh. were measured in double mutants between msg1 and axr1, both of which are auxin-resistant and defective in hypocotyl growth curvature induced upon unilateral application of auxin. the msg1 axr1 double mutants showed no auxin-induced growth curvature, that is, they exhibited the msg1 phenotype, though the axr1 defects were partial. hypocotyls of both the msg1 and axr1 mutants were partially defective in second-positive ph ... | 1999 | 9951732 |
| overexpression of rice phytochrome a partially complements phytochrome b deficiency in arabidopsis. | the red/far-red reversible phytochromes play a central role in regulating the development of plants in relation to their light environment. studies on the roles of different members of the phytochrome family have mainly focused on light-labile, phytochrome a and light-stable, phytochrome b. although these two phytochromes often regulate identical responses, they appear to have discrete photosensory functions. thus, phytochrome a predominantly mediates responses to prolonged far-red light, as wel ... | 1999 | 9951735 |
| prhj and hrpg, two new components of the plant signal-dependent regulatory cascade controlled by prha in ralstonia solanacearum. | hrp gene expression in the phytopathogenic bacterium ralstonia solanacearum gmi1000 is induced through the hrpb regulator in minimal medium and upon co-culture with plant cell suspensions. the putative outer membrane protein prha is specifically involved in hrp gene activation in the presence of plant cells and has been proposed to be a receptor of a plant-dependent signal transduction pathway. here, we report on the identification of two regulatory genes, hrpg and prhj, located at the right-han ... | 1999 | 9987125 |
| cdna sequence and overexpression of chloroplast chaperonin 21 from arabidopsis thaliana. | higher plant chloroplasts contain a 21-kda protein, chaperonin 21 (cpn21), that is a functional homolog of the chaperonin 10 (cpn10). the chloroplast cpn21 polypeptide consists of two cpn10-like domains fused together in tandem. we describe here the cdna sequence of the cpn21 (atcpn21) precursor protein from arabidopsis thaliana. the deduced amino acid sequence of the atcpn21 precursor protein, 253 amino acids long, shows 61% identity with the spinach cpn21 protein. the atcpn21 precursor protein ... | 1999 | 9989238 |
| the arabidopsis thaliana proton transporters, atnhx1 and avp1, can function in cation detoxification in yeast. | overexpression of the arabidopsis thaliana vacuolar h+-pyrophosphatase (avp1) confers salt tolerance to the salt-sensitive ena1 mutant of saccharomyces cerevisiae. suppression of salt sensitivity requires two ion transporters, the gef1 cl- channel and the nhx1 na+/h+ exchanger. these two proteins colocalize to the prevacuolar compartment of yeast and are thought to be required for optimal acidification of this compartment. overexpression of atnhx1, the plant homologue of the yeast na+/h+ exchang ... | 1999 | 9990049 |
| cloning, expression, and purification of cytidine deaminase from arabidopsis thaliana. | the complementary dna (cdna) coding for arabidopsis thaliana cytidine deaminase 1 (at-cda1) was obtained from the amplified a. thaliana cdna expression library, provided by r. w. davis (stanford university, ca). at-cda1 cdna was subcloned into the expression vector ptrc99-a and the protein, expressed in escherichia coli following induction with isopropyl 1-thio-beta-d-galactopyranoside, showed high cytidine deaminase activity. the nucleotide sequence showed a 903-bp open reading frame encoding a ... | 1999 | 10024464 |
| disulfide bond formation and folding of plant peroxidases expressed as inclusion body protein in escherichia coli thioredoxin reductase negative strains. | escherichia coli is widely used for the production of proteins, which are of interest in structure and function studies. the folding yield of inclusion body protein is, however, generally low (a few percent) for proteins such as the plant and fungal peroxidases, which contain four disulfide bonds, two ca2+ ions, and a heme group. we have studied the expression yield and folding efficiency of (i) a novel arabidopsis thaliana peroxidase, atp n; and (ii) barley grain peroxidase, bp 1. the expressio ... | 1999 | 10024473 |
| cloning and characterization of a maize cytochrome-b5 reductase with fe3+-chelate reduction capability. | we previously purified an nadh-dependent fe3+-chelate reductase (nfr) from maize roots with biochemical features of a cytochrome-b5 reductase (b5r) [sparla, bagnaresi, scagliarini and trost (1997) febs lett. 414, 571-575]. we have now cloned a maize root cdna that, on the basis of sequence information, calculated parameters and functional assay, codes for nfr. maize nfr has 66% and 65% similarity to mammal and yeast b5r respectively. it has a deduced molecular mass of 31.17 kda and a pi of 8.53. ... | 1999 | 10024528 |
| an arabidopsis 14-3-3 protein can act as a transcriptional activator in yeast. | the 14-3-3 proteins are a group of highly conserved and widely distributed eukaryotic proteins with diverse functions. one 14-3-3 protein, aft1 from arabidopsis thaliana, was found to be able to activate transcription in yeast. when fused to the dna-binding domain of a bacterial protein lexa, aft1 can activate transcription of reporter genes that contain lexa operator sequences in their promoters. although the in vivo function of aft1 is not completely known, its similarity to previously identif ... | 1999 | 10025948 |
| a plant 126-kda phosphatidylinositol 4-kinase with a novel repeat structure. cloning and functional expression in baculovirus-infected insect cells. | phosphatidylinositol metabolism plays a central role in signaling pathways in animals and is also believed to be of importance in signal transduction in higher plants. we report here the molecular cloning of a cdna encoding a previously unidentified 126-kda phosphatidylinositol (pi) 4-kinase (atpi4kbeta) from the higher plant arabidopsis thaliana. the novel protein possesses the conserved domains present in animal and yeast pi 4-kinases, namely a lipid kinase unique domain and a catalytic domain ... | 1999 | 10026194 |
| molecular cloning and characterization of three cdnas encoding putative mitogen-activated protein kinase kinases (mapkks) in arabidopsis thaliana. | we isolated three arabidopsis thaliana cdna clones (atmkk3, atmkk4 and atmkk5) encoding protein kinases with extensive homology to the mitogen-activated protein kinase kinases (mapkks) of various organisms in the catalytic domain. atmkk3 shows high homology (85% identity) to npk2, a tobacco mapkk homologue. atmkk4 and 5 are closely related to each other (84% identity). phylogenetic analysis showed that the plant mapkks constitute at least three subgroups. the recombinant atmkk3 and atmkk4 were e ... | 1998 | 10048483 |
| isolation of a gene encoding a glycosylated cytokinin oxidase from maize. | the major cytokinin oxidase in immature maize kernels was purified to homogeneity. selected tryptic peptides were used to design degenerate oligonucleotide primers for pcr isolation of a fragment of the oxidase gene. hybridization of the pcr fragment to a maize genomic library allowed isolation of a full-length cytokinin oxidase gene (ckx1). the gene encodes a protein of approximately 57 kda that possesses a signal peptide, eight consensus n-glycosylation sequences and a consensus fad binding se ... | 1999 | 10049708 |
| cloning and expression of a wheat (triticum aestivum l.) phosphatidylserine synthase cdna. overexpression in plants alters the composition of phospholipids. | we describe the cloning of a wheat cdna (tapss1) that encodes a phosphatidylserine synthase (pss) and provides the first strong evidence for the existence of this enzyme in a higher eukaryotic cell. the cdna was isolated on its ability to confer increased resistance to aluminum toxicity when expressed in yeast. the sequence of the predicted protein encoded by tapss1 shows homology to pss from both yeast and bacteria but is distinct from the animal pss enzymes that catalyze base-exchange reaction ... | 1999 | 10066765 |
| floral dip: a simplified method for agrobacterium-mediated transformation of arabidopsis thaliana. | the agrobacterium vacuum infiltration method has made it possible to transform arabidopsis thaliana without plant tissue culture or regeneration. in the present study, this method was evaluated and a substantially modified transformation method was developed. the labor-intensive vacuum infiltration process was eliminated in favor of simple dipping of developing floral tissues into a solution containing agrobacterium tumefaciens, 5% sucrose and 500 microliters per litre of surfactant silwet l-77. ... | 1998 | 10069079 |
| kcs1 encodes a fatty acid elongase 3-ketoacyl-coa synthase affecting wax biosynthesis in arabidopsis thaliana. | an arabidopsis fatty acid elongase gene, kcs1, with a high degree of sequence identity to fae1, encodes a 3-ketoacyl-coa synthase which is involved in very long chain fatty acid synthesis in vegetative tissues, and which also plays a role in wax biosynthesis. sequence analysis of kcs1 predicted that this synthase was anchored to a membrane by two adjacent n-terminal, membrane-spanning domains. analysis of a t-dna tagged kcs1-1 mutant demonstrated the involvement of the kcs1 in wax biosynthesis. ... | 1999 | 10074711 |
| eds1, an essential component of r gene-mediated disease resistance in arabidopsis has homology to eukaryotic lipases. | a major class of plant disease resistance (r) genes encodes leucine-rich-repeat proteins that possess a nucleotide binding site and amino-terminal similarity to the cytoplasmic domains of the drosophila toll and human il-1 receptors. in arabidopsis thaliana, eds1 is indispensable for the function of these r genes. the eds1 gene was cloned by targeted transposon tagging and found to encode a protein that has similarity in its amino-terminal portion to the catalytic site of eukaryotic lipases. thu ... | 1999 | 10077677 |
| channel-mediated high-affinity k+ uptake into guard cells from arabidopsis. | potassium uptake by higher plants is the result of high- or low-affinity transport accomplished by different sets of transporters. although k+ channels were thought to mediate low-affinity uptake only, the molecular mechanism of the high-affinity, proton-dependent k+ uptake system is still scant. taking advantage of the high-current resolution of the patch-clamp technique when applied to the small arabidopsis thaliana guard cells densely packed with voltage-dependent k+ channels, we could direct ... | 1999 | 10077678 |
| positive-negative selection and t-dna stability in arabidopsis transformation. | we have analysed the application of positive-negative selection for the selection of homologous recombination interactions between the chromosome and a t-dna molecule after transformation of plant cells. two different genomic loci in a cell suspension of arabidopsis thaliana were chosen to study gene targeting events. one was the chalcone synthase (chs) gene present as a single copy and the second an hemizygous chromosomally inserted t-dna containing the hpt gene, conferring resistance to hygrom ... | 1999 | 10080711 |
| molecular characterization of catalytic-subunit cdna sequences encoding protein phosphatases 1 and 2a and study of their roles in the gibberellin-dependent osamy-c expression in rice. | to understand the molecular mechanism of gibberellin-dependent gene regulation, the effect of three phosphatase inhibitors on the germination of rice seeds and the expression of a target gene, the alpha-amylase gene, osamy-c, were measured. we found that okadaic acid, microcystin-lr, and calyculin a, which are known to specifically inhibit ser/thr phosphatases 1 and 2a, strongly inhibit the expression of the osamy-c and may be involved in the germination of rice seeds. the protein phosphatase en ... | 1999 | 10080713 |
| the soybean enod40(2) promoter is active in arabidopsis thaliana and is temporally and spatially regulated. | the enod40 gene is induced early during rhizobium-legume symbiosis and has probably a primary role in the nodule organogenesis. in this paper we show that the 1.7 kb 5'-flanking region of the gmenod40(2) is able to drive the expression of a gusa-int marker in transgenic arabidopsis thaliana. the promoter activity is developmentally regulated and the major activity is detected in the root and in the stigma. | 1999 | 10080720 |
| detection of membrane-bound cytokinin-binding proteins in arabidopsis thaliana cells. | in order to isolate cytokinin-binding proteins (cbps), we have developed new affinity probes constituted of a cytokinin such as zeatin riboside ([9r]z) conjugated to a carrier protein. these probes were used for detecting cbps in an elisa procedure. the efficiency of the cytokinin conjugate in detecting cbps was controlled with protein model: proteins having an affinity for cytokinin such as the monoclonal anti-[9r]z antibodies did bind the cytokinin conjugate whereas proteins unable to bind cyt ... | 1999 | 10095789 |
| light regulates alternative splicing of hydroxypyruvate reductase in pumpkin. | hydroxypyruvate reductase (hpr) is a leaf peroxisomal enzyme that functions in the glycolate pathway of photorespiration in plants. we have obtained two highly similar cdnas for pumpkin hpr (hpr1 and hpr2). it has been revealed that two hpr mrnas might be produced by alternative splicing from a single type of pre-mrna. the hpr1 protein, but not the hpr2 protein, was found to have a targeting sequence into leaf peroxisomes at the c-terminus, suggesting that alternative splicing controls the subce ... | 1999 | 10097389 |
| mutational analysis of two arabidopsis thaliana cyclin-dependent kinases in fission yeast. | we have analyzed five mutant alleles of two cyclin-dependent kinases from arabidopsis thaliana, cdc2aat and cdc2bat, in schizosaccharomyces pombe. two of the five mutant alleles produced similar phenotypes for both cyclin-dependent kinases. the other three mutants caused phenotypes dependent on the particular cyclin-dependent kinase. of all the mutant alleles, only two were found to possess a detectable kinase activity. our mutational analysis lends further support for cdc2aat being the true ort ... | 1999 | 10100639 |
| expression of a gene for cyclophilin which contains an amino-terminal endoplasmic reticulum-targeting signal. | we isolated a novel gene for cyclophilin (cyp) first identified as an intracellular target of the immunosuppressant cyclosporin a and also known to have peptidyl-prolyl cis-trans isomerase (ppiase) activity, named atcyp5 from arabidopsis thaliana. atcyp5 encoded a polypeptide with 201 amino acids with a putative er-targeting signal sequence at its n-terminal, but without the typical er-retention signal in its c-terminal. in addition, atcyp5 protein contained a seven amino-acid long sequence whic ... | 1999 | 10189705 |
| mapping of 25 drought-inducible genes, rd and erd, in arabidopsis thaliana. | we mapped 25 arabidopsis thaliana drought-inducible genes. responsive to dehydration (rd) and early responsive to dehydration (erd), to the arabidopsis genome and compared map positions with those of mutants that show environmental stress response. we hybridized cic yeast artificial chromosome (yac) library filters with the cdnas and determined the map positions of 18 corresponding genes. we screened the p1 library with 7 other clones and analyzed segregation of their restriction fragment length ... | 1999 | 10189710 |
| metabolic engineering of cultured tobacco cells. | construction of a gene expression system in tobacco cultured cells (by2) was studied. a 925 bp promoter fragment of a heat-shock protein gene (hsp18.2) of arabidopsis thaliana showed clear heat-shock response of expression of the beta-glucuronidase (gus) reporter gene in by2 cells. similar results were observed in a 500 ml flask and 3-l jar fermentor. isolation of strong promoters in by2 cells was tried. cdna clones, in which the mrna level is high in log-phase cells and the copy number in the g ... | 1998 | 10191412 |
| plastidic pathway of serine biosynthesis. molecular cloning and expression of 3-phosphoserine phosphatase from arabidopsis thaliana. | in plants, ser is biosynthesized by two different pathways: a photorespiratory pathway via gly and a plastidic pathway via the phosphorylated metabolites from 3-phosphoglycerate. in contrast to the better characterization of the photorespiratory pathway at a molecular level, the molecular regulation and significance of the plastidic pathway are not yet well understood. an arabidopsis thaliana cdna encoding 3-phosphoserine phosphatase, the enzyme that is responsible for the conversion of 3-phosph ... | 1999 | 10196182 |
| conservation of functional features of u6atac and u12 snrnas between vertebrates and higher plants. | splicing of u12-dependent introns requires the function of u11, u12, u6atac, u4atac, and u5 snrnas. recent studies have suggested that u6atac and u12 snrnas interact extensively with each other, as well as with the pre-mrna by watson-crick base pairing. the overall structure and many of the sequences are very similar to the highly conserved analogous regions of u6 and u2 snrnas. we have identified the homologs of u6atac and u12 snrnas in the plant arabidopsis thaliana. these snrnas are significa ... | 1999 | 10199569 |
| molecular cloning and functional expression of gibberellin 2- oxidases, multifunctional enzymes involved in gibberellin deactivation. | a major catabolic pathway for the gibberellins (gas) is initiated by 2beta-hydroxylation, a reaction catalyzed by 2-oxoglutarate-dependent dioxygenases. to isolate a ga 2beta-hydroxylase cdna clone we used functional screening of a cdna library from developing cotyledons of runner bean (phaseolus coccineus l.) with a highly sensitive tritium-release assay for enzyme activity. the encoded protein, obtained by heterologous expression in escherichia coli, converted ga9 to ga51 (2beta-hydroxyga9) an ... | 1999 | 10200325 |
| genes for calcineurin b-like proteins in arabidopsis are differentially regulated by stress signals. | an important effector of ca2+ signaling in animals and yeast is the ca2+/calmodulin-dependent protein phosphatase calcineurin. however, the biochemical identity of plant calcineurin remained elusive. here we report the molecular characterization of atcbl (arabidopsis thaliana calcineurin b-like protein) from arabidopsis. the protein is most similar to mammalian calcineurin b, the regulatory subunit of the phosphatase. atcbl also shows significant similarity with another ca2+-binding protein, the ... | 1999 | 10200328 |
| plant genomics takes root, branches out. | for the past nine years, an international consortium of researchers have collaborated on a project to provide a full set of genomics tools for the model plant species arabidopsis thaliana. among the goals of this project were the complete sequence of the arabidopsis genome, which may be completed in the year 2000, four years ahead of schedule. arabidopsis was an appropriate choice as the first target of plant genomics because of its excellent genetics, outstanding research community and small ge ... | 1999 | 10203799 |
| the arabidopsis hal2-like gene family includes a novel sodium-sensitive phosphatase. | the yeast hal2 gene encodes a lithium- and sodium-sensitive phosphatase that hydrolyses 3'-phosphoadenosine-5'-phosphate (pap). salt toxicity in yeast results from hal2 inhibition and accumulation of pap, which inhibits sulphate assimilation and rna processing. we have investigated whether the model plant arabidopsis thaliana contains sodium-sensitive pap phosphatases. the arabidopsis hal2-like gene family is composed of three members: atahl and atsal2, characterized in the present work, and the ... | 1999 | 10205895 |
| regional insertional mutagenesis of genes on arabidopsis thaliana chromosome v using the ac/ds transposon in combination with a cdna scanning method. | for regional insertional mutagenesis of arabidopsis thaliana genes, we combined a cdna scanning method (hayashida et al. gene 1995; 165:155-161) and an ac/ds transposon designed for local mutagenesis, and evaluated this approach with two overlapping yeast artificial chromosome (yac) clones, cic7e11 and cic8b11, on a. thaliana chromosome 5. we applied a previously developed novel cdna selection method using dna latex particles (cdna scanning method) to the two yac clones and constructed two sub-l ... | 1999 | 10205900 |
| chloroplast cpn20 forms a tetrameric structure in arabidopsis thaliana. | chloroplast chaperonin 20 (cpn20) in higher plants is a functional homologue of the escherichia coli groes, which is a critical regulator of chaperonin-mediated protein folding. the cdna for a cpn20 homologue of arabidopsis thaliana was isolated. it was 958 bp long, encoding a protein of 253 amino acids. the protein was composed of an n-terminal chloroplast transit peptide, and the predicted mature region comprised two distinct groes domains that showed 42% amino acid identity to each other. the ... | 1999 | 10205903 |
| a cluster of aba-regulated genes on arabidopsis thaliana bac t07m07. | arabidopsis thaliana bac t07m07 encoding the abscisic acid-insensitive 4 (abi4) locus has been sequenced completely. it contains a 95,713-bp insert and 24 predicted genes. most putative genes were confirmed by gel-based rna profiling and a cluster of aba-regulated genes was identified. one of the 24 genes, designated pp2c5, encodes a putative protein phosphatase 2c. the encoded protein was expressed in escherichia coli, and its enzyme activity in vitro was confirmed. | 1999 | 10207155 |
| high yield purification and characterization of engineered human p450 1a2 and generation of immuno-inhibitor antibodies. | p450 s12, an engineered human p450 1a2 containing the 88-first amino-acids of the p450 1a1, demonstrates particularly high expression level in yeast while exhibiting catalytic properties very similar to the moderately expressed natural human p450 1a2. to facilitate p450 purification by nickel chelate chromatography, c-terminal extensions including histidine tags were tested. the -g(h)4 extension was found to be particularly efficient for permitting high expression levels without any catalytic al ... | 1999 | 10208644 |
| involvement of a chloroplast homologue of the signal recognition particle receptor protein, ftsy, in protein targeting to thylakoids. | we isolated an arabidopsis thaliana cdna whose translated product shows sequence similarity to the ftsy, a bacterial homologue of srp receptor protein. the arabidopsis ftsy homologue contains a typical chloroplast transit peptide. the in vitro-synthesized 37 kda ftsy homologue was imported into chloroplasts, and the processed 32 kda polypeptide bound peripherally on the outer surface of thylakoids. antibodies raised against the ftsy homologue also reacted with a thylakoid-bound 32 kda protein. t ... | 1999 | 10214972 |
| atsrp30, one of two sf2/asf-like proteins from arabidopsis thaliana, regulates splicing of specific plant genes. | sr proteins are nuclear phosphoproteins with a characteristic ser/arg-rich domain and one or two rna recognition motifs. they are highly conserved in animals and plants and play important roles in spliceosome assembly and alternative splicing regulation. we have now isolated and partially sequenced a plant protein, which crossreacts with antibodies to human sr proteins. the sequence of the corresponding cdna and genomic clones from arabidopsis revealed a protein, atsrp30, with strong similarity ... | 1999 | 10215626 |
| biosynthesis of phytochelatins in the fission yeast. phytochelatin synthesis: a second role for the glutathione synthetase gene of schizosaccharomyces pombe. | by complementation screening of a cadmium-sensitive schizosaccharomyces pombe mutant deficient in phytochelatin synthesis, but with 44% of the wild-type glutathione content, we cloned a dna fragment involved in phytochelatin synthesis. sequence analysis revealed that it encodes the second enzyme involved in glutathione (gsh) biosynthesis, glutathione synthetase (gsh2) (e.c.6.3.2.3, wang and oliver, 1997). the mutant allele shows a single base-pair exchange at the 3' end of the reading frame lead ... | 1999 | 10219997 |
| arabidopsis thaliana rna polymerase ii subunits related to yeast and human rpb5. | arabidopsis thaliana contains at least four genes that are predicted to encode polypeptides related to the rpb5 subunit found in yeast and human rna polymerase ii. this subunit has been shown to be the largest subunit common to yeast rna polymerases i, ii, and iii (rpabc27). more than one of these genes is expressed in arabidopsis suspension culture cells, but only one of the encoded polypeptides is found in purified rna polymerases ii and iii. this polypeptide has a predicted pi of 9.6, matches ... | 1999 | 10231567 |
| molecular cloning and expression analyses of mitochondrial and plastidic isoforms of cysteine synthase (o-acetylserine(thiol)lyase) from arabidopsis thaliana. | cysteine synthase, the key enzyme for fixation of inorganic sulfide, catalyses the formation of cysteine from o-acetylserine and inorganic sulfide. here we report the cloning of cdnas encoding cysteine synthase isoforms from arabidopsis thaliana. the isolated cdna clones encode for a mitochondrial and a plastidic isoform of cysteine synthase (o-acetylserine (thiol)-lyase, ec 4.2.99.8), designated cysteine synthase c (atcs-c, csase c) and b (atcs-b; csase b), respectively. atcs-c and atcs-b, havi ... | 1999 | 10319184 |
| maintenance of genomic methylation requires a swi2/snf2-like protein. | altering cytosine methylation by genetic means leads to a variety of developmental defects in mice, plants and fungi. deregulation of cytosine methylation also has a role in human carcinogenesis. in some cases, these defects have been tied to the inheritance of epigenetic alterations (such as chromatin imprints and dna methylation patterns) that do not involve changes in dna sequence. using a forward genetic screen, we identified a gene (ddm1, decrease in dna methylation) from the flowering plan ... | 1999 | 10319870 |
| the multiply-regulated gaba gene encoding the gaba permease of aspergillus nidulans: a score of exons. | we describe the cloning, sequence and expression of gaba, encoding the gamma-amino-n-butyrate (gaba) permease of the fungus aspergillus nidulans. sequence changes were determined for three up-promoter (gabi ) and six gaba loss-of-function mutations. the predicted protein contains 517 residues and shows 30.3% overall identity with a putative gaba permease of arabidopsis thaliana, 29.6% identity with the yeast choline transporter and 23.4% identity with the yeast uga4 gaba permease. structural pre ... | 1999 | 10320578 |
| identification and analysis of the arabidopsis thaliana bsh gene, a member of the snf5 gene family. | the multiprotein complexes involved in active dis-ruption of chromatin structure, homologous to yeast swi/snf complex, have been described for human and drosophila cells. in all swi/snf-class complexes characterised so far, one of the key components is the snf5-type protein. here we describe the isolation of a plant (arabidopsis thaliana ) cdna encoding a 27 kda protein which we named bsh, with high homology to yeast snf5p and its human (ini1) and drosophila (snr1) counterparts as well as to oth ... | 1999 | 10325430 |
| structural analysis and physical mapping of a pericentromeric region of chromosome 5 of arabidopsis thaliana. | the arabidopsis thaliana cic yac 2d2, 510 kb long and containing a small block of 180 bp satellite units was subcloned after ecor1 digestion in the pbluescript plasmid. one of these clones was mapped genetically in the pericentromeric region of chromosome 5. the analysis of 40 subclones of this yac showed that they all contain repeated sequences with a high proportion of transposable elements. three new retrotransposons, two ty-3 gypsy-like and one ty-1 copia, were identified in addition to two ... | 1999 | 10328626 |
| molecular analysis of mettl1, a novel human methyltransferase-like gene with a high degree of phylogenetic conservation. | a novel human gene, mettl1, has been identified by its sequence similarity to the yeast orf ydl201w. the human cdna and the genomic structure of mettl1 have been analyzed. the transcript contains 1292 nucleotides and codes for a protein of 276 amino acids. the gene consists of seven exons and extends over 3.5 kb. the six introns vary in length between 93 and 1137 nucleotides. the gene is transcribed in a large variety of organs and tissues and shows differential splicing of two exons, giving ris ... | 1999 | 10329009 |
| structure and regulation of opr1 and opr2, two closely related genes encoding 12-oxophytodienoic acid-10,11-reductases from arabidopsis thaliana. | the genes of two closely related 12-oxophytodienoic acid reductases (ec 1.3.1.42), opr1 and opr2, were identified on a 7079-bp-long genomic fragment from arabidopsis thaliana (l.) heynh. the organization of these two genes was determined and putative cis elements were identified. promoter-beta-glucuronidase (gus) fusions expressed in transgenic arabidopsis thaliana and nicotiana tabacum l. plants revealed differences in opr-promoter-driven gus expression in flowers. while the opr1 promoter direc ... | 1999 | 10333582 |
| optimized expression and catalytic properties of a wheat obtusifoliol 14alpha-demethylase (cyp51) expressed in yeast. complementation of erg11delta yeast mutants by plant cyp51. | cyp51s form the only family of p450 proteins conserved in evolution from prokaryotes to fungi, plants and mammals. in all eukaryotes, cyp51s catalyse 14alpha-demethylation of sterols. we have recently isolated two cyp51 cdnas from sorghum [bak, s., kahn, r.a., olsen, c. e. & halkier, b.a. (1997) plant j. 11, 191-201] and wheat [cabello-hurtado, f., zimmerlin, a., rahier, a., taton, m., derose, r., nedelkina, s., batard, y., durst, f., pallett, k.e. & werck-reichhart, d. (1997) biophys. biochem. ... | 1999 | 10336628 |
| recombinant production of the p10cks1at protein from arabidopsis thaliana and 13c and 15n double-isotopic enrichment for nmr studies. | the cks1at gene product, p10cks1at from arabidopsis thaliana, is a member of the cyclin-dependent kinase subunit (cks) family of small proteins. these proteins bind the cyclin-dependent kinase (cdk)/cyclin complexes and play an essential, but still not precisely known role in cell cycle progression. to solve the structure of p10cks1at, a protocol was needed to produce the quantity of protein large enough for nuclear magnetic resonance (nmr) spectroscopy. the first attempt to express cks1at in es ... | 1999 | 10336872 |
| padprt-2: a novel mammalian polymerizing(adp-ribosyl)transferase gene related to truncated padprt homologues in plants and caenorhabditis elegans. | until recently, poly(adp-ribosyl)ation was supposed to be confined only to polymerizing(adp-ribosyl)transferase/(adp-ribose)polymerase (e.c. 2.4.2.30). here, we present novel polymerizing(adp-ribosyl)transferase homologues from mouse and man that lack all of the n-terminal dna binding and brca1 c-terminus domains and will be designated polymerizing(adp-ribosyl)transferase-2 as distinguished from the classical polymerizing(adp-ribosyl)transferase (polymerizing(adp-ribosyl)transferase-1). the muri ... | 1999 | 10338144 |
| interaction of npr1 with basic leucine zipper protein transcription factors that bind sequences required for salicylic acid induction of the pr-1 gene. | the arabidopsis thaliana npr1 has been shown to be a key regulator of gene expression during the onset of a plant disease-resistance response known as systemic acquired resistance. the npr1 mutant plants fail to respond to systemic acquired resistance-inducing signals such as salicylic acid (sa), or express sa-induced pathogenesis-related (pr) genes. using npr1 as bait in a yeast two-hybrid screen, we identified a subclass of transcription factors in the basic leucine zipper protein family (ahbp ... | 1999 | 10339621 |
| complementation of plant mutants with large genomic dna fragments by a transformation-competent artificial chromosome vector accelerates positional cloning. | to accelerate gene isolation from plants by positional cloning, vector systems suitable for both chromosome walking and genetic complementation are highly desirable. therefore, we developed a transformation-competent artificial chromosome (tac) vector, pyltac7, that can accept and maintain large genomic dna fragments stably in both escherichia coli and agrobacterium tumefaciens. furthermore, it has the cis sequences required for agrobacterium-mediated gene transfer into plants. we cloned large g ... | 1999 | 10339623 |
| the arabidopsis thaliana hy1 locus, required for phytochrome-chromophore biosynthesis, encodes a protein related to heme oxygenases. | the hy1 mutants of arabidopsis thaliana fail to make the phytochrome-chromophore phytochromobilin and therefore are deficient in a wide range of phytochrome-mediated responses. because this defect can be rescued by feeding seedlings biliverdin ixalpha, it is likely that the mutations affect an enzyme that converts heme to this phytochromobilin intermediate. by a combination of positional cloning and candidate-gene isolation, we have identified the hy1 gene and found it to be related to cyanobact ... | 1999 | 10339624 |
| induction of rab18 gene expression and activation of k+ outward rectifying channels depend on an extracellular perception of aba in arabidopsis thaliana suspension cells. | important progress has been made regarding the characterization of the aba signalling components using genetic and molecular approaches (leung and giraudat, 1998). however, we do not yet know the mechanism of aba perception. conflicting results concerning the site of aba perception have been published. the prevailing view is that since aba controls many responses, different sites of perception for aba might exist. in order to establish the cellular localisation of the aba receptors in arabidopsi ... | 1999 | 10341440 |
| inter-organ signaling in plants: regulation of atp sulfurylase and sulfate transporter genes expression in roots mediated by phloem-translocated compound. | sulfate uptake and atp sulfurylase activity in the roots of arabidopsis thaliana and brassica napus were enhanced by s deprivation and reduced following resupply of so4(2-). similar responses occurred in split-root experiments where only a portion of the root system was s-deprived, suggesting that the regulation involves inter-organ signaling. phloem-translocated glutathione (gsh) was identified as the likely transducing molecule responsible for regulating so4(2-) uptake rate and atp sulfurylase ... | 1999 | 10341446 |
| characterisation of a novel gene family of putative cyclic nucleotide- and calmodulin-regulated ion channels in arabidopsis thaliana. | in plants, cyclic gmp is involved in signal transduction in response to light and gibberellic acid. for cyclic amp, a potential role during the plant cell cycle was recently reported. however, cellular targets for cyclic nucleotides in plants are largely unknown. here we report on the identification and characterisation of a new gene family in arabidopsis, which share features with cyclic nucleotide-gated channels from animals and inward-rectifying k+ channels from plants. the identified gene fa ... | 1999 | 10341447 |
| molecular characterization of a plant mitochondrial chaperone grpe. | escherichia coli dnak (hsp70) cooperates with dnaj and grpe in its essential role as a molecular chaperone. function of mitochondrial hsp70 (mhsp70) in protein folding and organellar import in eukaryotes is critically dependent on grpe. we cloned two genes from tobacco (nicotiana tabacum) by2 cells based on peptide sequences from a purified protein. the predicted amino acid sequences of both clones resembled that of grpe from e. coli and its homologues from eukaryotes, and a cdna clone from arab ... | 1999 | 10344193 |
| delta7-sterol-c5-desaturase: molecular characterization and functional expression of wild-type and mutant alleles. | an arabidopsis thaliana recessive monogenic mutant (ste1-1) presenting a deficiency of the delta7-sterol-c5(6)-desaturase step in the sterol pathway has been reported previously [12]. to further characterize ste1-1, arabidopsis, nicotiana tabacum and homo sapiens cdnas encoding delta7-sterol-c5(6)-desaturases were isolated and identified on the basis of their ability to restore ergosterol synthesis in erg3, a yeast null mutant whose gene encoding the delta7-sterol-c5(6)-desaturase was disrupted. ... | 1999 | 10344195 |
| analysis of arabidopsis genome sequence reveals a large new gene family in plants. | a detailed analysis of the currently available arabidopsis thaliana genomic sequence has revealed the presence of a large number of open reading frames with homology to the stigmatic self-incompatibility (s) genes of papaver rhoeas. the products of these potential genes are all predicted to be relatively small, basic, secreted proteins with similar predicted secondary structures. we have named these potential genes sph (s-protein homologues). their presence appears to have been largely missed by ... | 1999 | 10344198 |
| heterologous expression in saccharomyces cerevisiae of an arabidopsis thaliana cdna encoding mevalonate diphosphate decarboxylase. | sequence comparison with the mevalonate diphosphate decarboxylase (mvd) amino acid sequence of saccharomyces cerevisiae identified an est clone corresponding to a cdna that may encode arabidopsis thaliana mvd (atmvd1). this enzyme catalyses the synthesis of isopentenyl diphosphate, the building block of sterol and isoprenoid biosynthesis, and uses mevalonate diphosphate as a substrate. sequencing of the full-length cdna was performed. the predicted amino acid sequence presents about 55% identity ... | 1999 | 10344201 |
| characterization of the transcriptional activator cbf1 from arabidopsis thaliana. evidence for cold denaturation in regions outside of the dna binding domain. | a transcriptional activator, cbf1, from arabidopsis thaliana, which has the ap2 domain for dna binding and regulates the cold acclimation response, was overexpressed in escherichia coli, purified, and characterized. analyses of the interaction between cbf1 and the c-repeat/dehydration-responsive element by fluorescence measurement showed that cbf1 binds to c-repeat/dehydration-responsive element as a monomer irrespective of the temperature. cd spectra of the intact and truncated cbf1 proteins (1 ... | 1999 | 10347158 |
| [genetic effects in populations of plants growing in the zone of kyshtym and chernobyl accidents]. | studies to analyze the genetic processes in natural populations of plants were started on the territory of the east-ural radioactive trace (eurt) in 1962 and in the zone of the chernobyl accident in may 1986. the main directions of the genetic studies in both radioactive areas were similar: 1) study of the mutation process intensity depending on the dose and dose rate and analysis of dose-effect relationships for different genetic changes (point mutations, chromosome aberrations in mitosis and m ... | 1999 | 10347610 |
| the arabidopsis thaliana dhdps gene encoding dihydrodipicolinate synthase, key enzyme of lysine biosynthesis, is expressed in a cell-specific manner. | lysine synthesis in prokaryotes, some phycomycetes and higher plants starts with the condensation of l-aspartate-beta-semialdehyde (l-asa) and pyruvate into dihydrodipicolinic acid. the enzyme that catalyses this step, dihydrodipicolinate synthase (dhdps), is inhibited by the end-product lysine and is therefore thought to have a regulatory control on lysine synthesis. we have cloned and sequenced an arabidopsis thaliana dna fragment containing 900 bases upstream of the dhdps coding sequence. a t ... | 1999 | 10350084 |
| an example of intron junctional sliding in the gene families encoding squalene monooxygenase homologues in arabidopsis thaliana and brassica napus. | sequences of three arabidopsis thaliana and two brassica napus cdnas encoding squalene monooxygenase homologues (sqp1 and sqp2) are reported. southern analysis confirmed that these cdnas are derived from small gene families in both species. expression analysis indicates that sqp1 genes in b. napus are strongly expressed in leaves but not roots or developing seeds. comparison of cdna and genomic sequences indicate that the 3' splice site of an intron in these genes has undergone junctional slidin ... | 1999 | 10350086 |