| micron, a microsatellite-targeting transposable element in the rice genome. | we have isolated a new family of mobile elements, micron, which occur within microsatellites dispersed throughout the rice (oryza sativa) genome. the first of these segments, micron 001, was found in a microsatellite consisting of a (ta)n sequence upstream of the rice phytochrome a (phya) gene. pcr analysis of related rice species suggests that micron 001 integrated into this microsatellite locus prior to the divergence of the two wild species o. rufipogon and o. barthii from a common ancestor. ... | 2001 | 11713677 |
| potential of (gata)n microsatellites from rice for inter- and intra-specific variability studies. | the microsatellite, (gata)n has been frequently used for dna fingerprinting. however, very few attempts have been made to analyze (gata)n-containing loci in rice. | 2001 | 11710957 |
| haemoglobin (erythrogen) enhanced microcallus formation from protoplasts of indica rice (oryza sativa l.). | the beneficial effects have been studied of supplementing culture medium with 1:100-1:500 (v:v) of a commercial haemoglobin solution (erythrogen) on the mitotic division of cell suspension-derived protoplasts of indica rices (oryza sativa l.). protoplasts were cultured in liquid medium, at densities of 1.5 x 10(6) or 2.5 x 10(6) ml(-1), on nitrocellulose membranes overlaying a semi-solidified medium layer that was supplemented with both erythrogen and nurse cells of lolium multiflorum. the mean ... | 2001 | 11708663 |
| native and artificial reticuloplasmins co-accumulate in distinct domains of the endoplasmic reticulum and in post-endoplasmic reticulum compartments. | we compared the subcellular distribution of native and artificial reticuloplasmins in endosperm, callus, and leaf tissues of transgenic rice (oryza sativa) to determine the distribution of these proteins among endoplasmic reticulum (er) and post-er compartments. the native reticuloplasmin was calreticulin. the artificial reticuloplasmin was a recombinant single-chain antibody (scfv), expressed with an n-terminal signal peptide and the c-terminal kdel sequence for retrieval to the er (scfvt84.66- ... | 2001 | 11706200 |
| isolation and characterization of two genes encoding ubiquitin fused to a ribosomal protein of 53 amino acids in rice. | we isolated and determined the nucleotide sequences of two genes encoding ubiquitin fused to a ribosomal protein, ub-cep52, from rice (oryza sativa l.). the deduced amino-acid sequences of the two genes were found to be completely identical. the n-terminal region of 76 residues corresponds to ubiquitin, and the c-terminal region of 53 residues corresponds to ribosomal protein l40. a putative tata-like sequence, a polypyrimidine sequence, and a similar sequence to telo-box were found in the promo ... | 2001 | 11697144 |
| antisense inhibition of a bri1 receptor reveals additional protein kinase signaling components downstream to the perception of brassinosteroids in rice. | plants express a variety of proteins at the cell surface responsible for the transduction of regulatory information into the cell via receptors. in the present study, an attempt has been made to identify the components of the brassinosteroids (brs) signaling transduction cascades in transgenic rice (oryza sativa) expressing the antisense strand of osbri1 transcript. a 60 kda protein, immunologically characterized as mitogen-activated protein kinase (mapk), showed reduced phosphorylation activity ... | 2001 | 11696369 |
| antisense expression of a rice sucrose transporter ossut1 in rice (oryza sativa l.). | we analyzed the function of a rice sucrose transporter, ossut1, by using antisense rice. there was no difference between antisense and wild-type plants in carbohydrate content and photosynthetic ability of the flag leaves in the vegetative growth stage, suggesting that ossut1 may not play an important role in carbon metabolism, at least in these materials. | 2001 | 11673635 |
| activities of starch hydrolytic enzymes and sucrose-phosphate synthase in the stems of rice subjected to water stress during grain filling. | to understand the effect of water stress on the remobilization of prestored carbon reserves, the changes in the activities of starch hydrolytic enzymes and sucrose-phosphate synthase (sps) in the stems of rice (oryza sativa l.) during grain filling were investigated. two rice cultivars, showing high lodging-resistance and slow remobilization, were grown in the field and subjected to well-watered (ww, psi(soil)=0) and water-stressed (ws, psi(soil)=-0.05 mpa) treatments 9 d after anthesis (daa) ti ... | 2001 | 11604456 |
| expression of beta-expansins is correlated with internodal elongation in deepwater rice. | fourteen putative rice (oryza sativa) beta-expansin genes, os-expb1 through os-expb14, were identified in the expressed sequence tag and genomic databases. the dna and deduced amino acid sequences are highly conserved in all 14 beta-expansins. they have a series of conserved c (cysteine) residues in the n-terminal half of the protein, an hfd (histidine-phenylalanine-aspartate) motif in the central region, and a series of w (tryptophan) residues near the carboxyl terminus. five beta-expansin gene ... | 2001 | 11598238 |
| biochemical and genetic analysis of the effects of amylose-extender mutation in rice endosperm. | biochemical analysis of amylose-extender (ae) mutant of rice (oryza sativa) revealed that the mutation in the gene for starch-branching enzyme iib (beiib) specifically altered the structure of amylopectin in the endosperm by reducing short chains with degree of polymerization of 17 or less, with the greatest decrease in chains with degree of polymerization of 8 to 12. the extent of such change was correlated with the gelatinization properties of the starch granules, as determined in terms of sol ... | 2001 | 11598221 |
| visualization of the terminal structure of rice chromosomes 6 and 12 with multicolor fish to chromosomes and extended dna fibers. | high-resolution fluorescence in situ hybridization (fish) on interphase and pachytene nuclei, and extended dna fibers enabled microscopic distinction of dna sequences less than a few thousands of base pairs apart. we applied this technique to reveal the molecular organization of telomere ends in japonica rice (oryza sativa ssp. japonica), which consist of the arabidopsis type tttaggg heptameric repeats and the rice specific subtelomeric tandem repeat sequence a (trsa). southern hybridizations of ... | 2001 | 11587512 |
| the purple leaf (pl) locus of rice: the pl(w) allele has a complex organization and includes two genes encoding basic helix-loop-helix proteins involved in anthocyanin biosynthesis. | the purple leaf (pl) locus of rice (oryza sativa l.) affects regulation of anthocyanin biosynthesis in various plant tissues. the tissue-specific patterns of anthocyanin pigmentation, together with the syntenic relationship, indicate that the rice pl locus may play a role in the anthocyanin pathway similar to the maize r/b loci. we isolated two cdnas showing significant identity to the basic helix-loop-helix (bhlh) proteins found in the maize r gene family. osb1 appeared to be allelic to the pre ... | 2001 | 11577193 |
| marker-assisted selection for identification of plant regeneration ability of seed-derived calli in rice (oryza sativa l.). | quantitative trait loci (qtl), associated with the ability of plant regeneration from seed-derived callus of rice, were mapped using a recombinant inbred (ri) population from milyang 23/gihobyeo. each flanking marker, rz474 and rz575, tightly linked to two qtls (qsgr-3-1 and qsgr-3-2) that are located on chromosome 3 was used in marker-assisted selection (mas). these markers were tested on ir 36/mg ri036 (f3), milyang 23/mg ri036 (f3), and forty-one rice cultivars. a restriction fragment length ... | 2001 | 11561716 |
| [qtl dissection of panicle number per plant and spikelet number per panicle in rice (oryza sativa l.)]. | the genetic mechanism underlying panicle number per plant (pn), spikelet number per panicle (snp) and its related traits in rice was analysed using 292 f13 rils from the cross of lemont/teqing and a complete linkage map with 272 molecular markers. the rils showed tremendous transgressive segregation for all traits studied. the weak negative correlation between pn and snp was observed. fifty-one qtls and 45 epistatic qtl pairs affecting these traits were identified, collectively explaining over 6 ... | 2001 | 11554350 |
| [the comparison of genetic divergences and its relationships to heterosis revealed by ssr and rflp markers in rice (oryza sativa l.)]. | genetic divergences of 57 entries from 6 ecotypes of rice were surveyed by pcr analysis with 48 pairs of ssr and by southern analysis by 50 rflp probes. it was indicated that ssr markers detected polymorphism efficiently in comparison to rflp markers, considering the allele numbers per locus and average gene diversity. among all of 1,596 pairs, 1,452 pairs of genetic distances based on ssr data (gdssr) were higher than the genetic distance based on rflp data (gdrflp) by average of 0.2492. the av ... | 2001 | 11554348 |
| nuclear- and chloroplast-microsatellite variation in a-genome species of rice. | simple sequence length polymorphism analysis was carried out to reveal microsatellite variation and to clarify the phylogenetic relationships among a-genome species of rice. total dna from 29 cultivars (23 oryza sativa and 6 o. glaberrima) and 30 accessions of wild a-genome species (12 o. rufipogon, 5 o. glumaepatula, 2 o. longistaminata, 6 o. meridionalis, and 5 o. barthii) was used as a template for pcr to detect 24 nuclear and 10 chloroplast microsatellite loci. microsatellite allelic diversi ... | 2001 | 11550902 |
| high-resolution two-dimensional electrophoresis separation of proteins from metal-stressed rice (oryza sativa l.) leaves: drastic reductions/fragmentation of ribulose-1,5-bisphosphate carboxylase/oxygenase and induction of stress-related proteins. | employing high-resolution two-dimensional electrophoresis (2-de), we studied changes in the rice leaf protein patterns, in response to applied heavy and alkaline metals, important environmental pollutants in our surroundings. drastic changes in 2-de protein patterns after treatment with copper, cadmium, and mercury, over control were found, including changes in the morphology of the leaf segments. changes in the major leaf photosynthetic protein, ribulose-1,5-bisphosphate carboxylase/oxygenase ( ... | 2001 | 11545414 |
| transfer from long to short photoperiods affects production efficiency of day-neutral rice. | the day-neutral, semidwarf rice (oryza sativa l.) cultivar ai-nan-tsao was grown in a greenhouse under summer conditions using high-pressure sodium lamps to extend the natural photoperiod. after allowing 2 weeks for germination, stand establishment, and thinning to a consistent planting density of 212 plants/m2, stands were maintained under continuous lighting for 35 or 49 days before shifting to 8- or 12-h photoperiods until harvest 76 days after planting. non-shifted control treatments consist ... | 1999 | 11542385 |
| the effect of the external medium on the gravitropic curvature of rice (oryza sativa, poaceae) roots. | the roots of rice seedlings, growing in artificial pond water, exhibit robust gravitropic curvature when placed perpendicular to the vector of gravity. to determine whether the statolith theory (in which intracellular sedimenting particles are responsible for gravity sensing) or the gravitational pressure theory (in which the entire protoplast acts as the gravity sensor) best accounts for gravity sensing in rice roots, we changed the physical properties of the external medium with impermeant sol ... | 1997 | 11541059 |
| are contents of rubisco, soluble protein and nitrogen in flag leaves of rice controlled by the same genetics? | genetic relations among the contents of rubisco, soluble protein and total leaf nitrogen (n) in leaves of rice (oryza sativa l.) were studied by quantitative trait loci (qtl) analysis with a population of backcross inbred lines (bils) of japonica nipponbarexindica kasalath. the ratio of rubisco to total leaf n in leaves is the main target in improving photosynthetic n-use efficiency in plants. qtls controlling rubisco content were not detected near qtls for total leaf n content. these results in ... | 2001 | 11520871 |
| computational and experimental analysis of microsatellites in rice (oryza sativa l.): frequency, length variation, transposon associations, and genetic marker potential. | a total of 57.8 mb of publicly available rice (oryza sativa l.) dna sequence was searched to determine the frequency and distribution of different simple sequence repeats (ssrs) in the genome. ssr loci were categorized into two groups based on the length of the repeat motif. class i, or hypervariable markers, consisted of ssrs > or =20 bp, and class ii, or potentially variable markers, consisted of ssrs > or =12 bp <20 bp. the occurrence of class i ssrs in end-sequences of ecori- and hindiii-dig ... | 2001 | 11483586 |
| grain sink strength may be related to the poor grain filling of indica-japonica rice (oryza sativa) hybrids. | the physiological and biochemical factors contributing to poor grain filling of indica-japonica rice (oryza sativa l.) hybrids were studied by analyzing the role of grain sink strength in dry matter accumulation of grains of two types of rice cultivars, yayou 2 (an indica-japonica hybrid) and yanjing 2 (a japonica cultivar). carbon dioxide enrichment and plant hormone application were imposed at anthesis and the number of endosperm cells, dry matter accumulation and the activities of some sugar- ... | 2001 | 11473706 |
| two types of replication protein a 70 kda subunit in rice, oryza sativa: molecular cloning, characterization, and cellular & tissue distribution. | replication protein a (rpa), which is comprised of three subunits, is an important factor involved in dna replication, repair, and transcription. we isolated and characterized 70 and 32 kda subunits of rpa from rice (oryza sativa cv. nipponbare) termed osrpa70a and osrpa32. osrpa70a shows a low level of homology with osrpa1 which was isolated from deepwater rice (oryza sativa cv. pin gaew 56), previously. we also succeeded to isolate osrpa70b which is homologue to osrpa1 from oryza sativa cv. ni ... | 2001 | 11470540 |
| ospaa2, a distinct alpha 1 subunit gene for the 20s proteasome in rice (oryza sativa l.). | the 20s proteasome is the proteolytic complex that is involved in removing abnormal proteins and other diverse biological functions. the 20s proteasome is constituted of 28 subunits arranged in four rings of seven subunits, and exists as a hollow cylinder. the two outer rings and the two inner rings are composed of seven different alpha and beta type subunits, respectively, giving an alpha 7 beta 7 beta 7 alpha 7 structure. we previously reported the primary structures of the 14 proteasomal subu ... | 2001 | 11470506 |
| involvement of cytochrome p-450 enzyme activity in the selectivity and safening action of pyrazosulfuron-ethyl. | to investigate the selectivity and safening action of the sulfonylurea herbicide pyrazosulfuron-ethyl (pse), pyrazosulfuron-ethyl o-demethylase (pseod) activity involving oxidative metabolism by cytochrome p-450 was studied in rice (oryza sativa l cv nipponbare) and cyperus serotinus rottb. cytochrome p-450-dependent activity was demonstrated by the use of the inducers 1,8-naphthalic anhydride and ethanol, the herbicides pse, bensulfuron-methyl, dimepiperate and dymron, or the inhibitor piperony ... | 2001 | 11455659 |
| uptake and translocation of carpropamid in rice (oryza sativa l). | translocation of the antiblast compound, carpropamid, was investigated in rice using [14c]carpropamid. when applied to the seed, carpropamid was not only readily absorbed but was translocated to different parts of the seedlings emerging from treated seeds. a substantial portion of fungicide appeared to be exuded onto the leaf surface. in 21-day-old plants grown from [14c]carpropamid-treated seeds, 27.2% of the radioactivity isolated from leaves was present on the surface of lamina. this exuded f ... | 2001 | 11455653 |
| synthesis of hemoglobins in rice (oryza sativa var. jackson) plants growing in normal and stress conditions. | in rice (oryza sativa var. jackson) at least three copies of hemoglobin (hb) gene exist. rice hb1 and hb2 genes are differentially expressed in roots and leaves from mature plants. we used polyclonal antibodies raised to recombinant rice hb1 and western blotting to analyze the synthesis of hbs in rice plants growing under normal or stress conditions. results showed that rice hbs are synthesized in coleoptiles, seminal roots and embryos from seeds germinated for 6 days, and also in leaves and roo ... | 2001 | 11448759 |
| gene tagging in rice: a high throughput system for functional genomics. | rice, with its small genome size and well-characterized molecular information, is an ideal model plant for cereal genomics research. sequence of the rice (oryza sativa) genome will be determined by the international rice genome sequencing project (irgsp) in the near future. therefore, a large population of mutant plants should be required for adequately assigning function to the abundant sequence information. here we summarize strategies as well as the progress that has been made in producing ge ... | 2001 | 11448751 |
| rapd, rflp and sslp analyses of phylogenetic relationships between cultivated and wild species of rice. | rapd, rflp, nuclear sslp and chloroplast sslp analyses were carried out to clarify the phylogenetic relationships among a-genome species of rice. in total, 12 cultivars of oryza sativa (4 japonica, 3 javanica and 5 indica), one cultivar of o. glaberrima, and 17 wild accessions (12 o. rufipogon, 2 o. glumaepatula, 1 o. longistaminata, 1 o. meridionalis and 1 o. barthii) were used. their banding patterns were scored and compared to evaluate the similarity between accessions. genetic differentiatio ... | 2001 | 11434461 |
| mapping of qtls associated with cytosolic glutamine synthetase and nadh-glutamate synthase in rice (oryza sativa l.). | ninety-eight backcross inbred lines (bc1f6) developed between nipponbare, a japonica rice, and kasalath, an indica rice were employed to detect putative quantitative trait loci (qtls) associated with the contents of cytosolic glutamine synthetase (gs1; ec 6.3.1.2) and nadh-glutamate synthase (nadh-gogat; ec 1.4.1.14) in leaves. immunoblotting analyses showed transgressive segregations toward lower or greater contents of these enzyme proteins in these backcross inbred lines. seven chromosomal qtl ... | 2001 | 11432939 |
| anoxic stress leads to hydrogen peroxide formation in plant cells. | hydrogen peroxide (h2o2) was detected cytochemically in plant tissues during anoxia and re-oxygenation by transmission electron microscopy using its reaction with cerium chloride to produce electron dense precipitates of cerium perhydroxides. anoxia-tolerant yellow flag iris (iris pseudacorus) and rice (oryza sativa), and anoxia-intolerant wheat (triticum aestivum) and garden iris (iris germanica) were used in the experiments. in all plants tested, anoxia and re-oxygenation increased h2o2 in pla ... | 2001 | 11432936 |
| a framework for sequencing the rice genome. | rice is an important food crop and a model plant for other cereal genomes. the clemson university genomics institute framework project, begun two years ago in anticipation of the now ongoing international effort to sequence the rice genome, is nearing completion. two bacterial artificial chromosome (bac) libraries have been constructed from the oryza sativa cultivar nipponbare. over 100,000 bac end sequences have been generated from these libraries and, at a current total of 28 mbp, represent 6. ... | 2001 | 11387975 |
| modulation in the activity of purified tonoplast h+-atpase by tonoplast glycolipids prepared from cultured rice (oryza sativa l. var. boro) cells. | glycolipids, phospholipids, and neutral lipids were extracted from the tonoplast fraction of cultured rice cells (oryza sativa l. var. boro). acyl steryl glucoside (asg) and glucocerebroside (glccer) were also prepared from this fraction. we determined the effects of these tonoplast lipids on the activity of h+-atpase which was delipidated and purified from the tonoplast fraction. exogenously added tonoplast phospholipids stimulated the activity of purified tonoplast h+-atpase, but tonoplast gly ... | 2001 | 11382818 |
| cellular compartmentation of ammonium assimilation in rice and barley. | this review describes immunolocalization studies of the tissue and cellular location of glutamine synthetase (gs; ec 6.3.1.2) and glutamate synthase (fd gogat; ec 1.4.7.1 and nadh-gogat; ec 1.4.1.14) proteins in roots and leaves of rice (oryza sativa l.) and barley (hordeum vulgare l.). in rice, cytosolic gs (gs1) protein was distributed homogeneously through all cells of the root. nadh gogat protein was strongly induced and its cellular location altered by ammonium treatment, becoming concentra ... | 2001 | 11373307 |
| isolation and molecular characterization of the cop1 gene homolog from rice, oryza sativa l. subsp. indica var. pusa basmati 1. | the cop1 (constitutive photomorphogenic 1) gene has been identified earlier from dicot species namely arabidopsis, tomato and pea. the protein encoded by this gene acts as a molecular switch that negatively regulates the transition from the skotomorphogenic to the photomorphogenic mode of plant development. we have isolated and characterized the cop1 homolog from a monocot species, i.e. rice (var. pusa basmati 1). all the functional domains (zn-binding ring finger motif, coiled-coil region, wd-4 ... | 2001 | 11347904 |
| chloroplast fructose-1,6-bisphosphatase from oryza differs in salt tolerance property from the porteresia enzyme and is protected by osmolytes. | salinity exerted a distinctly differential effect on fructose-1,6-bisphosphatase (ec. 3.1.3.11) isolated from salt-sensitive and salt-tolerant rice (oryza sativa) varieties. cytosolic and chloroplastic isoforms of the enzyme from salt-sensitive rice seedlings exhibited decreased catalytic activity during growth in the presence of salt. furthermore, chloroplastic fructose 1,6-bisphosphatase purified from salt-sensitive (o. sativa cv. ir26) and from the wild halophytic rice porteresia coarctata di ... | 2001 | 11337074 |
| real time visualization of 13n-translocation in rice under different environmental conditions using positron emitting ttacer imaging system. | the ammonium ion is an indispensable nitrogen source for crops, especially paddy rice (oryza sativa l. cv nipponbare). until now, it has been impossible to measure ammonium uptake and nitrogen movement in plants in real time. using the new technologies of petis (positron emitting tracer imaging system) and pmps (positron multi-probe system), we were able to visualize the real time translocation of nitrogen and water in rice plants. we used positron-emitting 13n-labeled ammonium (13nh4+) and 15o- ... | 2001 | 11299355 |
| enzymic feruloylation of arabinoxylan-trisaccharide by feruloyl-coa:arabinoxylan-trisaccharide o-hydroxycinnamoyl transferase from oryza sativa. | feruloyl-coa:arabinoxylan-trisaccharide o-hydroxycinnamoyl transferase, which catalyzes the transfer of ferulic acid from fer-coa to arabinoxylan-trisaccharide in the formation of feruloyl arabinoxylan-trisaccharide (fer-axx), has been found in an ionically bound fraction and a cytosol fraction of suspension-cultured rice (oriza sativa l. cv. nipponbare) cells. analysis of reaction products by high-performance liquid chromatography showed the formation of product a, which is one of the transfer ... | 2001 | 11289614 |
| new rice mutants lacking glutelin alpha-1 subunit. | four rice (oryza sativa l.) mutant lines lacking glutelin alpha-1 subunit were obtained by screening the progenies of fertilized egg treatment with mnu. sds-page and ief analyses showed that the mutants without pi6.82 polypeptide in common while forming/increasing other polypeptide indicating that the mutants were controlled by structural genes. ief analysis also suggested that the polypeptides of pi6.82 and pi8.58 derived from the same glutelin precursor. the mutants are considered to be useful ... | 2001 | 11280996 |
| characterization of euploid backcross progenies derived from interspecific hybrids between oryza sativa and o. eichingeri by restriction fragment length polymorphism (rflp) analysis and genomic in situ hybridization (gish). | restriction fragment length polymorphism (rflp) analysis and gish (genomic in situ hybridization) were performed on euploid plants derived from crosses between oryza sativa (2n = 24, aa) and two brown planthopper-resistant accessions of o. eichingeri (2n = 24, cc). after screening with 164 rflp markers, 60 of the 67 euploid plants were identified as introgression lines, each carrying 1-6 small o. eichingeri segments integrated on chromosomes 1, 2, 6, or 10. in the somatic chromosome preparations ... | 2001 | 11269361 |
| quantitative trait loci mapping associated with plant regeneration ability from seed derived calli in rice (oryza sativa l.). | quantitative trait loci (qtls), which are associated with the ability of plant regeneration from seed derived calli, were detected using a recombinant inbred (ri) population from a cross between 'milyang 23 (toingil)' and 'gihobyeo (japonica)' in rice (oryza sativa l.). a tongil type cultivar, 'milyang 23', has a lower frequency of callus induction and plant regeneration than those of japonica 'gihobyeo'. transgressive segregations were observed for the callus induction rate and plant regenerati ... | 2001 | 11266122 |
| comparison of waxy gene regulation in the endosperm and pollen in oryza sativa l. | the waxy (wx) gene controls amylose synthesis in rice (oryza sativa) and its expression is regulated organ-specifically. the wx gene is expressed in the endosperm and pollen but not in other organs. in order to know whether wx gene regulation is the same in the endosperm and pollen, we compared expression patterns of the rice wx gene in these two organs by immunoblot analysis. we focused on the allelic differences (wxa and wxb), cool temperature response and effects of the mutation at the du loc ... | 2000 | 11245217 |
| a rice membrane-bound calcium-dependent protein kinase is activated in response to low temperature. | calcium-dependent protein kinases (cdpks) are found in various subcellular localizations, which suggests that this family of serine/threonine kinases may be involved in multiple signal transduction pathways. cdpks are believed to be involved in the response of plants to low temperatures, but the precise role in the signal transduction pathway is largely unknown. previous reports described changes in cdpks' mrna levels in response to cold treatment, but whether these changes are accompanied by in ... | 2001 | 11244123 |
| nonsense-mediated decay of mutant waxy mrna in rice. | two rice (oryza sativa) waxy mutations of the japonica background were shown to contain approximately 20% of the fully spliced mrna relative to the wild type. sequencing analysis of the entire waxy genes of the two mutants revealed the presence of premature translation termination codons in exon 2 and exon 7. these results indicated that the lower accumulation of fully spliced rna in the mutants was caused by nonsense-mediated decay (nmd), which is an rna surveillance system universally found in ... | 2001 | 11244118 |
| comparative sequence analysis of colinear barley and rice bacterial artificial chromosomes. | colinearity of a large region from barley (hordeum vulgare) chromosome 5h and rice (oryza sativa) chromosome 3 has been demonstrated by mapping of several common restriction fragment-length polymorphism clones on both regions. one of these clones, wg644, was hybridized to rice and barley bacterial artificial chromosome (bac) libraries to select homologous clones. one bac from each species with the largest overlapping segment was selected by fingerprinting and blot hybridization with three additi ... | 2001 | 11244114 |
| toward integration of comparative genetic, physical, diversity, and cytomolecular maps for grasses and grains, using the sorghum genome as a foundation. | the small genome of sorghum (sorghum bicolor l. moench.) provides an important template for study of closely related large-genome crops such as maize (zea mays) and sugarcane (saccharum spp.), and is a logical complement to distantly related rice (oryza sativa) as a "grass genome model." using a high-density rflp map as a framework, a robust physical map of sorghum is being assembled by integrating hybridization and fingerprint data with comparative data from related taxa such as rice and using ... | 2001 | 11244113 |
| mutator transposase is widespread in the grasses. | although the mutator (mu) system is well characterized in maize (zea mays), very little is known about this highly mutagenic system of transposons in other grasses. mutator is regulated by the mudr class of elements, which encodes two genes, one of which, mudra, has similarity to a number of bacterial transposases. experiments in our laboratory, as well as database searches, demonstrate that mudra sequences are ubiquitous and diverse in the grasses. in several species it is clear that multiple p ... | 2001 | 11244110 |
| screening of the rice viviparous mutants generated by endogenous retrotransposon tos17 insertion. tagging of a zeaxanthin epoxidase gene and a novel ostatc gene. | the rice (oryza sativa) retrotransposon tos17 is one of a few active retrotransposons in plants and its transposition is activated by tissue culture. here, we present the characterization of viviparous mutants of rice induced by tissue culture to demonstrate the feasibility of the use of retrotransposon tos17 as an endogenous insertional mutagen and cloning of the tagged gene for forward genetics in unraveling the gene function. two mutants were shown to be caused by the insertion of tos17. osab ... | 2001 | 11244106 |
| rice bioinformatics. analysis of rice sequence data and leveraging the data to other plant species. | rice (oryza sativa) is a model species for monocotyledonous plants, especially for members in the grass family. several attributes such as small genome size, diploid nature, transformability, and establishment of genetic and molecular resources make it a tractable organism for plant biologists. with an estimated genome size of 430 mb (arumuganathan and earle, 1991), it is feasible to obtain the complete genome sequence of rice using current technologies. an international effort has been establis ... | 2001 | 11244096 |
| the lax1 and frizzy panicle 2 genes determine the inflorescence architecture of rice by controlling rachis-branch and spikelet development. | we have analyzed two mutants that exhibit altered panicle architecture in rice (oryza sativa l.). in lax1-2, which is a new and stronger allele of the previously reported lax mutant, initiation and/or maintenance of rachis-branches, lateral spikelets, and terminal spikelets was severely prevented. in situ hybridization analysis using osh1, a rice knotted1 (kn1) ortholog, confirmed the absence of lateral meristems in lax1-2 panicles. these defects indicate that the lax1 gene is required for the i ... | 2001 | 11237465 |
| [qtl analysis for epistatic effects and qtl x environment interaction effects on final height of rice (oryza sativa l.)]. | qtls with epistatic effects and environmental interaction effects for final height of rice were studied by mixed-model based qtl mapping with a doubled haploid population from ir64/azucena in four environments. the results demonstrated the importance of epistasis as a genetic basis of the quantitative traits and also revealed several important features of this phenomenon. in the results, 100 per cent of qtls were involved in epistasis, of which 64 per cent were found with significant additive ef ... | 2001 | 11233257 |
| characterization of a rice (oryza sativa l.) bowman-birk proteinase inhibitor: tightly light regulated induction in response to cut, jasmonic acid, ethylene and protein phosphatase 2a inhibitors. | the bowman-birk (bb) family of proteinase inhibitors (pi), initially reported from legume seeds, and thereafter also from wounded alfalfa and maize leaves appear to be regulated in similar ways as the extensively characterized pi i and pi ii family from dicots. here, we report a first characterization of the expression profiles of a rice (oryza sativa l. cv. nipponbare) bbpi gene, osbbpi, which is part of a multigene family as demonstrated by genomic southern hybridization. osbbpi was found to b ... | 2001 | 11223257 |
| behavior of cinosulfuron in paddy surface waters, sediments, and ground water. | cinosulfuron (3-(4,6-dimethoxy-1,3,5-triazin-2-yl)-1-[2-(2-methoxyethoxy)-phenylsulfonyl]-urea) is a sulfonylurea herbicide used to control a wide range of broadleaf weeds in rice (oryza sativa l.). a 2-yr field study was conducted in northwest italy to determine the effect of cinosulfuron on surface and subsoil waters in rice paddies. cinosulfuron was applied at 70 g a.i. ha(-1) on 35 ha of flooded rice. after the treatment, the change in herbicide concentration over time was studied by analyzi ... | 2015 | 11215644 |
| [qtls analysis of tiller angle in rice (oryza sativa l.)]. | tiller angle is one of important characters that constitute plant type with great significance in breading. a pair of japonica/indica lines, which were significantly different in tiller angle, were used in this study. a dh population were constructed via anther culture of f1 hybrids. the tiller angles of 115 dh lines were measured. qtl analysis was conducted based on the constructed molecular linkage map. three qtls (qta-9a, qta-9b and qta-12) were detected on chromosome 9 and 12 respectively, t ... | 2001 | 11209708 |
| [developmental genetic analysis of brown rice thickness of indica rice (oryza sativa l.)]. | analysis of developmental genetic effects for brown rice thickness (brt) trait in indica rice (oryza sativa l.) at four different filling stages was conducted and a developmental genetic model and corresponding statistical approaches for quantitative traits of triploid endosperm in cereal crops was used. the results indicated that the diploid maternal plant, triploid endosperm and cytoplasmic genetic effects were important for brt trait at all filling stages of rice and those effects were the ma ... | 2000 | 11192430 |
| regulation of proline accumulation in detached rice leaves exposed to excess copper. | accumulation of proline in response to excess cu was studied in detached leaves of rice (oryza sativa). cuso(4) was effective in inducing proline accumulation in detached rice leaves under both light and dark conditions. cuso(4) and cucl(2) were equally effective in inducing proline accumulation, indicating that proline accumulation is induced by cu. sulfate salts of mg, mn, and fe were ineffective in inducing proline accumulation in detached rice leaves. excess cu had no effect on relative wate ... | 2001 | 11164600 |
| a comparative molecular-physiological study of submergence response in lowland and deepwater rice. | survival of rice (oryza sativa) upon an extreme rise of the water level depends on rapid stem elongation, which is mediated by ethylene. a genomic clone (os-acs5) encoding 1-aminocyclopropane-1-carboxylic acid (acc) synthase, which catalyzes a regulatory step in ethylene biosynthesis, has been isolated from cv ir36, a lowland rice variety. expression was induced upon short- and long-term submergence in cv ir36 and in cv plai ngam, a thai deepwater rice variety. under hypoxic conditions, abscisic ... | 2001 | 11161052 |
| sugar coordinately and differentially regulates growth- and stress-related gene expression via a complex signal transduction network and multiple control mechanisms. | in plants, sugars are required to sustain growth and regulate gene expression. a large set of genes are either up- or down-regulated by sugars; however, whether there is a common mechanism and signal transduction pathway for differential and coordinated sugar regulation remain unclear. in the present study, the rice (oryza sativa cv tainan 5) cell culture was used as a model system to address this question. sucrose and glucose both played dual functions in gene regulation as exemplified by the u ... | 2001 | 11161045 |
| quantitative trait loci for component physiological traits determining salt tolerance in rice. | rice (oryza sativa) is sensitive to salinity, which affects one-fifth of irrigated land worldwide. reducing sodium and chloride uptake into rice while maintaining potassium uptake are characteristics that would aid growth under saline conditions. we describe genetic determinants of the net quantity of ions transported to the shoot, clearly distinguishing between quantitative trait loci (qtl) for the quantity of ions in a shoot and for those that affect the concentration of an ion in the shoot. t ... | 2001 | 11154348 |
| [genetic study of plant height of tall plant mutant mh-1 in rice (oryza sativa l.)]. | mh-1 is a tall plant mutant induced by irradiation from semi-dwarfed variety guichao 2. the genetic analyses were carried out through the f1, f2, f3 progenies and test-crossed f1 on mh-1 crossed with materials with sd-1 gene, non-allelic gene to sd-1 and common tall plant. the results indicate that the induced tall plant trait of mh-1 is controlled by a recessive inhibiting gene, named tentatively i-sd-1(t), that can regulate the expression of sd-1 gene but not of non-allelic gene to sd-1. the v ... | 2000 | 11147349 |
| gibberellin biosynthesis: metabolic evidence for three steps in the early 13-hydroxylation pathway of rice. | [14c4]ga53, [14c4]ga44, and [2h2/14c4]ga19 were injected separately into seedlings of rice (oryza sativa) using a dwarf mutant (d35) that has low levels of endogenous gibberellins (gas). after 8 h incubation, the shoots were extracted and the labeled metabolites were identified by full-scan gas chromatography mass spectrometry (gc-ms) and kovats retention indices (kris). our results document the metabolic sequence, ga53-->ga44-->ga19-->ga20 and the presence of endogenous ga53, ga44, ga19, ga20 a ... | 2000 | 11117879 |
| rice (oryza sativa l.) ospr1b gene is phytohormonally regulated in close interaction with light signals. | strategies evolved by plants to counteract a variety of biotic/abiotic stresses include induction of genes encoding pathogenesis-related (pr) protein, in particular the pr class 1 (pr1) gene family, widely used in stress response studies. in spite of its immense importance as a pr family member, and an accepted gene marker in plant disease/defense in dicots, little is known about rice pr1 genes. recently, we cloned and characterized the first ospr1a (rice acidic pr1) gene (agrawal et al. (2000) ... | 2000 | 11097833 |
| involvement of calcium-dependent protein kinase in rice (oryza sativa l.) lamina inclination caused by brassinolide. | promotive effect of brassinolide (bl) on green lamina inclination was concentration-dependent when excised rice (oryza sativa l.) lamina was floated on bl solution under continuous light conditions. protein kinase inhibitor staurosporine and ca2+ channel blocker lacl3 could completely, while ca2+ chelator egta could partially inhibit the lamina inclination caused by bl. two protein kinases with apparent molecular masses of 45 and 54 kda were detected using an in-gel kinase assay with histone iii ... | 2000 | 11092909 |
| identification of rice varieties with high tolerance or sensitivity to lead and characterization of the mechanism of tolerance. | pb inhibits plant growth. to study pb tolerance in rice (oryza sativa), we screened 229 varieties for pb tolerance or sensitivity. three-day-old seedlings were treated for 12 d with 20 microm pb solution. based on the dry weight of the root, three pb-tolerant (var ch-55, var kh-2j, var kumnung) and three pb-sensitive (var aixueru, var c-9491, var milyang23) rice varieties were selected. the root biomasses of the tolerant varieties were approximately 10-fold higher than those of the sensitive one ... | 2000 | 11080279 |
| [qtls and epistasis underlying rice (oryza sativa l.) panicle length in different genetic background and environments]. | a double haploid (dh) population and a recombinant inbred (ri) population derived from a cross between a japonica male parent azucena and indica female parents, ir64 and ir1552 respectively, were used in both field and pot experiments for detecting qtls and epistasis for rice panicle length in different genetic background and different environments. panicle length (pl) was measured at maturity. qtls for pl were detected using single marker analysis and interval mapping. epistasis effects on the ... | 2000 | 11051720 |
| selective inhibition of reactions involved in methanogenesis and fatty acid production on rice roots. | washed excised roots of rice (oryza sativa) produced h(2), ch(4) and fatty acids (millimolar concentrations of acetate, propionate, butyrate; micromolar concentrations of isovalerate, valerate) when incubated under anoxic conditions. surface sterilization of the root material resulted in the inactivation of the production of ch(4), a strong reduction of the production of fatty acids and a transient (75 h) but complete inhibition of the production of h(2). radioactive bicarbonate was incorporated ... | 2000 | 11053733 |
| expression of alpha-expansin genes in young seedlings of rice (oryza sativa l.). | rice is the only cereal in which germination and coleoptile elongation occur in hypoxia or anoxia. little is known of the molecular basis directly underlying coleoptile cell extension. in this paper, we describe the expression of alpha-expansin genes in embryos during seed development and young seedlings grown under various oxygen concentrations. the genes os-exp2 and os-exp1 were predominantly expressed in the developing seeds, mainly in newly developed leaves, coleoptiles, and seminal roots. t ... | 2000 | 11030545 |
| ethylene induces epidermal cell death at the site of adventitious root emergence in rice. | in deepwater rice (oryza sativa), adventitious root primordia initiate at the nodes as part of normal development. emergence of the roots is dependent on flooding of the plant and is mediated by ethylene action. root growth was preceded by the induced death of epidermal cells of the node external to the tip of the root primordium. cell death proceeded until the epidermis split open. through this crack the root eventually emerged. induced death was confined to nodal epidermal cells covering the t ... | 2000 | 11027711 |
| changes in lipid peroxidation, the redox system and atpase activities in plasma membranes of rice seedling roots caused by lanthanum chloride. | highly purified plasma membranes were isolated by aqueous two-phase partitioning from rice (oryza sativa) seedling roots. the effects of lanthanum chloride (lacl3) on the activities of lipid peroxidation, the redox system and h+-atpase, ca2+-atpase of plasma membranes were studied. the lipid peroxidation of plasma membranes could be depressed by certain low concentrations of lacl3 and enhanced by high concentrations of lacl3, while the lipid peroxidation was also dependent on the plasma membrane ... | 2000 | 11016404 |
| the cell cycle genes cyca1;1 and cdc2os-3 are coordinately regulated by gibberellin in planta. | internodal growth of deepwater rice (oryza sativa l.) can achieve rates of up to 10 mm h(-1). in submergence-induced plants, gibberellic acid activates the cell division cycle first at the g1 --> s phase transition with a subsequent increase in mitotic activity. the proteins cyca1;1 and cdc2os-3 are the regulatory and catalytic subunits, respectively, of cyclin-dependent protein kinases (cdks) which are central to cell cycle regulation. both genes are regulated by gibberellic acid in a coordinat ... | 2000 | 10987556 |
| analysis of opt8511 rapd fragments closely linked with cold sensitivity at seedling stage in rice (oryza sativa l.). | opt8(511) was confirmed to be strongly associated with cold sensitivity of rice by random amplified polymorphic dna (rapd) analysis for the cold tolerance with 94 f2 population crossed with 'dular' (cold sensitive cultivar) and 'toyohatamochi' (cold resistant cultivar). a dna marker from the rapd fragment, opt8(511), has been cloned with genomic dna from rice cultivar ('dular') and the nucleotide sequence has been determined. the nucleotide sequence revealed that the putative open reading frame ... | 2000 | 10987133 |
| photosynthesis and translocation of assimilates in rice plants following phloem feeding by the planthopper nilaparvata lugens (homoptera: delphacidae). | experiments were conducted to measure the effect of feeding by the planthopper nilaparvata lugens (stål) on photosynthesis and the translocation of assimilates in rice plants, oryza sativa l. we used mature japonica rice plants and applied the 13co2 feeding method to evaluate those physiological effects. the photosynthetic rate was suppressed by n. lugens infestation, especially at the lower leaf position, with rates 30% lower than that of control plants at the booting stage. leaf nitrogen conce ... | 2000 | 10985030 |
| changes in photosynthetic carbon flow in transgenic rice plants that express c4-type phosphoenolpyruvate carboxykinase from urochloa panicoides. | a cdna encoding phosphoenolpyruvate carboxykinase (pck) of urochloa panicoides (a pck-type c4 plant) was expressed in rice (oryza sativa cv tsukinohikari) plants under the control of the promoter of a maize (zea mays) gene for phosphoenolpyruvate carboxylase or pyruvate, orthophosphate dikinase with the transit peptide of the small subunit of rubisco. crude extracts prepared from the green leaves of transgenic plants had high pck activity and the newly expressed pck was localized in chloroplasts ... | 2000 | 10982431 |
| sugar uptake and transport in rice embryo. expression of companion cell-specific sucrose transporter (ossut1) induced by sugar and light. | we investigated sugar uptake and transport in rice (oryza sativa) embryo during grain germination. endogenous sugar levels, accumulation of starch granules, and gene expression of a rice sucrose transporter (ossut1) were examined using rice embryos germinated with or without exogenous sugar supply. starch granules remarkably accumulated in the cells around vascular bundles as a consequence of the sugar taken up by the embryos, indicating that the taken-up sugars are transiently converted into st ... | 2000 | 10982424 |
| molecular cloning and expression of a phospholipid hydroperoxide glutathione peroxidase homolog in oryza sativa. | a cdna encoding putative phospholipid hydroperoxide glutathione peroxidase (phgpx) was isolated from rice using rapid amplification of cdna ends. this cdna, designated ricphgpx, includes an open reading frame encoding a protein of 169 amino acids which shares about 60% and 50% amino acid sequence identity with plant and mammalian phgpxs, respectively. the gene is expressed at a relative high level in flag leaves and the expression can be markedly induced by oxidative stress, suggesting that the ... | 2000 | 10978528 |
| coronatine elicits phytoalexin production in rice leaves (oryza sativa l.) in the same manner as jasmonic acid. | the phytotoxin coronatine induced the accumulation of the flavonoid phytoalexins sakuranetin and momilactone a in rice leaves. coronatine-inducible sakuranetin production was under the control of kinetin and ascorbic acid (asa), as observed with jasmonic acid (ja). the effects of kinetin and asa on the activity of coronatine indicated that coronatine might elicit sakuranetin production in a manner similar to ja. the similarity of both their structures and the manner of elicitation of coronatine ... | 2000 | 10975503 |
| mechanism of the chilling-induced decrease in proton pumping across the tonoplast of rice cells. | the atp-generated proton pumping across tonoplast vesicles from chilling-sensitive boro rice (oryza sativa l. var. boro) cultured cells was markedly decreased by chilling at 5 degrees c for 3 d. the membrane fluidity of core hydrophobic and surface hydrophilic regions of the lipid bilayer was measured by steady-state fluorescence depolarization of 1,6-diphenyl-1,3,5-hexatriene and trimethylammonium 1,6-diphenyl-1,3,5-hexatriene and by electron spin resonance spectroscopy of 16- and 5-doxyl stear ... | 2000 | 10965940 |
| molecular cloning and characterization of cdnas encoding two isoforms of ribulose-1,5-bisphosphate carboxylase/oxygenase activase in rice (oryza sativa l.). | ribulose-1,5-bisphosphate carboxylase/oxygenase (rubisco) activase catalyzes the activation of rubisco in vivo. two full length cdnas designated as osrcaa1 and osrcaa2 encoding two rubisco activase isoforms of 47 and 43 kda, respectively, have been cloned and characterized. the two isoforms were 99% identical, the 47 kda isoform having an additional 33 amino acids and a 5 amino acid substitution at the carboxyl terminus. the deduced amino acid sequences of osrcaa1 and osrcaa2 showed 73-89% ident ... | 2000 | 10965036 |
| physiological responses to oxidative and heavy metal stress in seedlings of rice paddy, oryza sativa l. | | 2000 | 10960144 |
| identification of 4-o-5'-coupled diferulic acid from insoluble cereal fiber. | the extracts of saponified cereal fibers of whole grains of corn (zea mays cv. microsperma koern.), wheat (triticum aestivum l.), spelt (triticum spelta l.), and rice (oryza sativa l.) were investigated for dehydrodimers of ferulic acid using gas-liquid chromatography (glc) with mass spectrometric detection (glc-ms) and flame ionization detection (glc-fid). in addition to the 8,5'-, 8, 8'-, 5,5'-, and 8-o-4'-coupled diferulic acids previously identified from other plant materials the 4-o-5'-coup ... | 2000 | 10956086 |
| enhanced tolerance to salt stress in transgenic rice that overexpresses chloroplast glutamine synthetase. | the potential role of photorespiration in the protection against salt stress was examined with transgenic rice plants. oryza sativa l. cv. kinuhikari was transformed with a chloroplastic glutamine synthetase (gs2) gene from rice. each transgenic rice plant line showed a different accumulation level of gs2. a transgenic plant line, g39-2, which accumulated about 1.5-fold more gs2 than the control plant, had an increased photorespiration capacity. in another line, g241-12, gs2 was almost lost and ... | 2000 | 10949377 |
| specific accumulation of polysaccharide-linked hydroxycinnamoyl esters in the cell walls of irregularly shaped and collapsed internode parenchyma cells of the dwarf rice mutant fukei 71. | we examined a novel rice mutant, fukei 71 (oryza sativa l.), for alterations in the levels of hydroxycinnamoyl esters that are linked to cell wall polysaccharides and lignin units. in this mutant, a recessive mutation at a single locus caused the collapse of parenchyma cells in the internodes. light microscopy revealed that the abnormal walls of internode parenchyma cells of fukei 71 were stained by the mäule reaction, which is specific for syringyl units in phenolic compounds. these walls were ... | 2000 | 10945348 |
| aberrant chloroplasts in transgenic rice plants expressing a high level of maize nadp-dependent malic enzyme. | nadp-dependent malic enzyme (nadp-me) is a major decarboxylating enzyme in nadp-me-type c4 species such as maize and flaveria. in this study, chloroplastic nadp-me was transferred to rice (oryza sativa l.) using a chimeric gene composed of maize nadp-me cdna under the control of rice light-harvesting chlorophyll-a/b-binding protein (cab) promoter. there was a 20- to 70-fold increase in the nadp-me activity in leaves of transgenic rice compared to that in wild-type rice plants. immunocytochemical ... | 2000 | 10945221 |
| developing prolamine protein bodies are associated with the cortical cytoskeleton in rice endosperm cells. | the mrnas that encode the prolamine storage proteins in rice (oryza sativa l.) endosperm cells are enriched on the surface of the prolamine protein bodies (pbs), a subcellular structure consisting of a prolamine intracisternal granule surrounded by rough endoplasmic reticulum membrane. previous biochemical studies (d.g. muench et al., 1998, plant physiol. 116: 559-569) have shown that prolamine mrnas may be anchored to the pb surface via the cytoskeleton. to better understand the mechanism and r ... | 2000 | 10945217 |
| field evaluation of seed production, shattering, and dormancy in hybrid populations of transgenic rice (oryza sativa) and the weed, red rice (oryza sativa). | the genetic and agronomic consequences of transferring glufosinate (liberty) herbicide resistance from transgenic rice (oryza sativa l.) lines to the noxious weed red rice (oryza sativa l.) were evaluated under field conditions. replicated field trials in louisiana (la) and arkansas (ar) were conducted in 1997 to evaluate ten vegetative and reproductive traits of eight f(2) populations produced from controlled crosses of two transgenic, glufosinate-resistant rice lines and four red rice biotypes ... | 2000 | 10940465 |
| role of jasmonate in the rice (oryza sativa l.) self-defense mechanism using proteome analysis. | exogenously applied jasmonic acid (ja) was used to study changes in protein patterns in rice (oryza sativa l.) seedling tissues, to classify these changes, and to assign a role for these changes, in order to define the role of ja in the rice self-defense mechanism. high resolution two-dimensional polyacrylamide gel electrophoretic analysis revealed induction of new proteins in both leaf and stem tissues after ja treatment, with the major protein spots further analyzed through n-terminal and inte ... | 2000 | 10939463 |
| photosynthesis, plant growth and n allocation in transgenic rice plants with decreased rubisco under co2 enrichment. | ribulose-1,5-bisphosphate carboxylase (rubisco) efficiency for co2-saturated photosynthesis was examined in leaves of rice (oryza sativa l.). the amount of rubisco in a leaf was calculated to be 30-55% in excess for the light-saturated rate of photosynthesis at 100 pa co2. long-term exposure to co2 enrichment decreased the amount of rubisco protein. however, n was not reallocated from decreased rubisco to other components limiting photosynthesis, and the decrease in rubisco was simply due to a d ... | 2000 | 10938846 |
| trivalent ions activate abscisic acid-inducible promoters through an abi1-dependent pathway in rice protoplasts. | the plant hormone abscisic acid (aba) mediates many vital processes in plant growth and development, including seed dormancy, cell division, water use efficiency, and adaptation to drought, salinity, chilling, pathogen attack, and uv light. our understanding of aba signal transduction is fragmentary and would benefit from specific and facile probes of the process. protoplasts from rice (oryza sativa l. cv ir54) embryonic suspension cultures cotransformed with effector plasmids encoding the maize ... | 2000 | 10938371 |
| a novel rice (oryza sativa l.) acidic pr1 gene highly responsive to cut, phytohormones, and protein phosphatase inhibitors. | a novel rice acidic pathogenesis-related (pr) class 1 cdna (ospr1a) was isolated from jasmonic acid (ja)-treated rice seedling leaf. the ospr1a cdna is 830 bp long and contains an open reading frame of 507 nucleotides encoding 168 amino acid residues with a predicted molecular mass of 17,560 and pi of 4.4. the deduced amino acid sequence of ospr1a has a high level of identity with acidic and basic pr1 proteins from plants. southern analysis revealed that ospr1a is a member of a multigene family. ... | 2000 | 10903912 |
| stereochemical fate of c-26 and c-27 during the conversion of isofucosterol to sitosterol and of 24-methylenecholesterol to campesterol and dihydrobrassicasterol in oryza sativa cell cultures. | administration of pro-r-methyl-13c-labeled isofucosterol to cultured cells of oryza sativa revealed that the pro-r and pro-s methyls at c-25 become the pro-r and pro-s methyls at c-25 of sitosterol, respectively. similar administration experiments using pro-s-methyl-13c-labeled 24-methylenecholesterol established that the pro-r and pro-s methyls at c-25 of 24-methylenecholesterol become the pro-r and pro-s methyls of campesterol, and the pro-s and pro-r methyls of dihydrobrassicasterol, respecti ... | 2000 | 10897478 |
| possible involvement of phosphoinositide-ca2+ signaling in the regulation of alpha-amylase expression and germination of rice seed (oryza sativa l.). | we have studied the effects of neomycin, a potent inhibitor of inositol phospholipid-specific phospholipase c (plc), on the germination of rice seed and the gibberellin-induced expression of alpha-amylase in the aleurone layer and the scutellar tissues. it was shown that, in the absence of exogenous ca2+, neomycin markedly reduced the germination speed and seedling growth of rice seeds and inhibited the gibberellin-induced expression of alpha-amylase in both secretory tissues. in addition, neomy ... | 2000 | 10845452 |
| quantification of total genomic dna and selected repetitive sequences reveals concurrent changes in different dna families in indica and japonica rice. | this paper describes a fluorescence in situ hybridization (fish) analysis of three different repetitive sequence families, which were mapped to mitotic metaphase chromosomes and extended dna fibers (edfs) of the two subspecies of rice (oryza sativa), indica and japonica (2n = 2x = 24). the repeat families studied were (1) the tandem repeat sequence a (trsa), a functionally non-significant repeat; (2) the [ttta-ggg]n telomere sequence, a non-transcribed, tandemly repeated but functionally signifi ... | 2000 | 10821172 |
| naringenin 7-o-methyltransferase involved in the biosynthesis of the flavanone phytoalexin sakuranetin from rice (oryza sativa l.). | an inducible s-adenosyl-l-methionine:naringenin 7-o-methyltransferase (nomt) catalyzing the methylation of naringenin to sakuranetin, a major rice phytoalexin was purified approximately 985-fold from ultraviolet (uv)-irradiated rice leaves. the enzyme is not found in healthy tissues and was purified to a nearly homogeneous preparation in one step using adenosine-agarose affinity chromatography, with 1 g rice leaves (uv-irradiated) as starting material. gel filtration chromatography resulted in a ... | 2000 | 10814825 |
| the rice r gene family: two distinct subfamilies containing several miniature inverted-repeat transposable elements. | the r and b genes of maize regulate the anthocyanin biosynthetic pathway and constitute a small gene family whose evolution has been shaped by polyploidization and transposable element activity. to compare the evolution of regulatory genes in the distinct but related genomes of rice and maize, we previously isolated two r homologues from rice (oryza sativa). the ra1 gene on chromosome 4 can activate the anthocyanin pathway, whereas the rb gene, of undetermined function, maps to chromosome 1. in ... | 2000 | 10809440 |
| increasing anther culture efficiency in rice (oryza sativa l.) using anthers from ratooned plants. | anther culture response for the variety taipei-309 was compared using anthers of ratooned and non-ratooned plants. anthers were plated onto n6 liquid media with 0, 2, 5, and 10 mg l(-1) aba, respectively. after 5 days in culture, the media were removed and n6 medium without aba was added. a higher number of pre-mitotic p-pollen grains were observed in anthers from ratooned plants. a significant synergistic effect was found between anthers from ratooned plants/aba concentrations and the increase ... | 2000 | 10808066 |
| hormonal cross-talk between auxin and ethylene differentially regulates the expression of two members of the 1-aminocyclopropane-1-carboxylate oxidase gene family in rice (oryza sativa l.). | two cdna clones, pos-aco2 and pos-aco3, encoding 1-aminocyclopropane-1-carboxylate (acc) oxidase were isolated from rice seedling cdna library. pos-aco3 is a 1,299 bp full-length clone encoding 321 amino acids (mr=35.9 kda), while pos-aco2 is 1,072 bp long and is a partial cdna clone encoding 314 amino acids. these two deduced amino acid sequences share 70% identity, and display a high degree of sequence identity (72-92%) with previously isolated pos-aco1 of deepwater rice. the chromosomal locat ... | 2000 | 10805599 |
| identification and chromosomal localization of a transcriptionally active retrotransposon of ty3-gypsy type in rice. | a dna fragment representing a transcriptionally active retrotransposon of ty3-gypsy type was isolated and characterized from rice (oryza sativa l.). the fragment (named rire9) includes the coding sequences for the c-terminal part of the rnase h domain and the n-terminal part of the integrase domain in the polyprotein region. northern blot hybridization indicated that this element was expressed in rice leaves and stems, suggesting that it is potentially active to transpose under normal growth con ... | 2000 | 10791831 |
| transcript levels of the nuclear-encoded respiratory genes in rice decrease by oxygen deprivation: evidence for involvement of calcium in expression of the alternative oxidase 1a gene. | we investigated the effect of oxygen on the expressions of respiratory genes encoded in the nuclear and mitochondrial genomes of rice (oryza sativa l.). hypoxic treatment decreased the transcript levels of nuclear-encoded, but not mitochondrial-encoded respiratory genes. the effects of ruthenium red (an inhibitor of ca(2+) fluxes from organelles) and/or cacl(2) on plants under hypoxic conditions suggested that ca(2+) is a physiological transducer of a low-oxygen signaling pathway for expression ... | 2000 | 10767423 |
| differences in the sensitivity to uvb radiation of two cultivars of rice (oryza sativa l.) based on observation of long-lived radicals. | free radicals with a long lifetime were observed in the leaves of two rice cultivars (oryza sativa l.), sasanishiki (uvb resistant) and norin-1 (uvb sensitive), by electron spin resonance spectroscopy. the leaves of both cultivars grown with visible light show very similar esr spectra composed of radical 1 (r1) and radical 2 (r2), which may be attributable to p700 cation radicals in the reaction center of photosystem i, and tyrosine cation radicals in the reaction center of photosystem ii, respe ... | 1999 | 10748576 |
| mapping of centromeric regions on the molecular linkage map of rice (oryza sativa l.) using centromere-associated sequences. | genetic mapping of centromeres has been a challenge for plant geneticists. the objective of this study was to develop a new strategy for determining the locations of centromeric regions on genetic maps by mapping centromere-associated sequences, to make it possible to define the centromeric region of each chromosome as a single mendelian locus on the molecular linkage map. two dna probes containing sequences specifically associated with the centromeres of grass species were used for genetic mapp ... | 2000 | 10732686 |