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rice gibberellin-binding phosphoprotein structurally related to ribulose-1,5-bisphosphate carboxylase/oxygenase activase.a gibberellin a (ga)-binding protein was identified from rice (oryza sativa l.) leaves by a ligand-binding assay. the dissociation constant of ga-binding protein and ga complex was about 100 nm. this protein has a relative molecular mass of 47 000 and an isoelectric point of 5.1. the partial amino acid sequence of the protein was determined for 54 residues from both the n-terminal and internal regions. a sequence homology search indicated that the amino acid sequence of ga-binding protein was ho ...19968612816
effect of culture methods on the regeneration of albino rice (oryza sativa l.) plantlets.in our study, we investigated the effects of regeneration conditions on both green and albino rice plants (oryza sativa l.). the regeneration frequency of an albino cell line was compared to a normal cell line obtained from mature seed under two kinds of culture conditions; namely, the static culture on semi-solid regeneration medium and the suspension culture in liquid regeneration medium. the albino cell line, from which only albino plantlets were regenerated, was induced from the albino leaf ...199624178525
molecular mapping of quantitative trait loci in japonica rice.rice (oryza sativa l.) molecular maps have previously been constructed using interspecific crosses or crosses between the two major subspecies: indica and japonica. for japonica breeding programs, however, it would be more suitable to use intrasubspecific crosses. a linkage map of 129 random amplified polymorphic dna (rapd) and 18 restriction fragment length polymorphism (rflp) markers was developed using 118 f2 plants derived from a cross between two japonica cultivars with high and low seedlin ...199618469902
characterization of four induced chromosome deficiencies in rice (oryza sativa l.).four rice (oryza sativa l.) deficiencies, involving chromosomes 4 (df4), 8 (df8), and 11 (df11-1, df11-2), were studied. the deficiencies were induced by means of the pseudodominance technique, i.e., strains carrying one or more recessive marker genes were fertilized with irradiated pollen of a strain carrying normal alleles at corresponding loci. no characteristic morphological features were found in the deficiencies, as compared with the normal f1 plants in the progeny. the deficiencies showed ...199618469895
variations in glutelin and high molecular weight endosperm proteins among subspecies of rice (oryza sativa l.) detected by two-dimensional gel electrophoresis.variations in endosperm polypeptides among 16 cultivars of rice were analyzed by two-dimensional gel electrophoresis. one glutelin alpha-subunit (alpha 8) with a molecular mass of 32.5 kda was exclusively present in indica cultivars. by contrast, the glutelin alpha 3 subunit, with a molecular mass of 32 kda, was present only in japonica and javanica cultivars. glutelin alpha-subunits alpha 5a and alpha 5b, which have a molecular mass of 32 kda and slightly different isoelectric points, differed ...19968752866
evidence for genomic changes in transgenic rice (oryza sativa l.) recovered from protoplasts.the occurrence of genomic modifications in transgenic rice plants recovered from protoplasts and their transmission to the self-pollination progeny has been verified with the random amplified polymorphic dna (rapd) approach. the plant was the indica-type rice (oryza sativa l.) cultivar chinsurah boro ii. the analysed material was: (1) microspore-derived embryogenic rice cells grown in suspension culture, (2) transgenic plants recovered from protoplasts produced from the cultured cells and (3) th ...19968866891
cool-temperature-induced chlorosis in rice plants.we have established an experimental system for mimicking the phenomenon of cool-temperature-induced chlorosis (ctic) in rice plants (oryza sativa l.). rice seedlings were initially grown in darkness under cool-temperature conditions and then exposed to light and warm conditions to follow the expression of ctic. induction of ctic in the sensitive cultivar (cv surjamukhi) was bimodally dependent on the temperatures experienced during the initial growth in darkness. ctic was maximally induced betwe ...19968819872
isolation and characterization of two cdna clones for mrnas that are abundantly expressed in immature anthers of rice (oryza sativa l.).the relationship between the length of anthers and the stage of development of microspores was examined in rice (oryza sativa l. cv. hayayuki). anthers of < or = 2 mm and 2.1-2.2 mm in length and those ready to dehiscence were determined to be at the uninucleate, binucleate and trinucleate microspore stage, respectively. two cdnas (yy1 and yy2), representing genes that are specifically expressed in anthers at the uninucleate microspore stage, were isolated and characterized. yy1 cdna encoded an ...19968704128
molecular cloning and characterization of a cdna for the beta subunit of a g protein from rice.we isolated a cdna for the beta subunit of a heterotrimeric g protein from rice (oryza sativa l. cv. nipponbare). the amino acid sequence deduced from the cdna was 76% an 94% homologus to the sequences of the beta subunits from arabidopsis and maize (ag beta 1 and zg beta 1), respectively.19968665097
export of β-1,3-glucanase from mutant rice cells rechallenged and stressed with lysine plus threonine.mutant rice cells (oryza sativa l.) grown in liquid suspension cultures exported greater quantities of protein and β-glucanases than controls. these mutants were isolated from anther calli resistant to 1 mm lysine plus threonine (lt), regenerated and reestablished as cell suspension cultures from seeds. cellular protein levels are genetically conditioned, and the levels of extracellular proteins and enzyme activities are inversely related to that of the cellular portions. the rechallenge of cell ...199624166174
identification of qtls affecting traits of agronomic importance in a recombinant inbred population derived from a subspecific rice cross.to detect qtls controlling traits of agronomic importance in rice, two elite homozygous lines 9024 and lh422, which represent the indica and japonica subspecies of rice (oryza sativa), were crossed. subsequently a modified single-seed-descent procedure was employed to produce 194 recombinant inbred lines (f8). the 194 lines were genotyped at 141 rflp marker loci and evaluated in a field trial for 13 quantitative traits including grain yield. transgressive segregants were observed for all traits ...199624166172
two new loci for hybrid sterility in cultivated rice (oryza sativa l.).female gamete abortion in indica-japonica crosses of rice was earlier identified to be due to an allelic interaction at the s-5 locus on chromosome 6. recently, in other crosses of rice, similar allelic interactions were found at loci designated as s-7 and s-8, located on chromosomes 7 and 6 respectively. all of them are independent of each other. at the s-5 locus, indica and japonica rice have s-5 (i) and s-5 (j) alleles respectively and javanicas, such as ketan nangka, have a neutral allele s- ...199624166167
diauxic growth in rice suspension cells grown on mixed carbon sources of acetate and glucose.diauxic growth was observed in rice (oryza sativa l.) suspension cells growing on acetate (10 mm) and glucose (10 mm). cells used acetate during the first growth phase and the acetate level in the medium was rapidly decreased, whereas the level of glucose remained essentially unchanged. after acetate was depleted from the medium, cells started to use glucose, forming the second growth phase. it appears that uptake of [14c]glucose was repressed during the first growth phase and became active duri ...199612226198
involvement of jasmonic acid in elicitor-induced phytoalexin production in suspension-cultured rice cells.it has been suggested that jasmonic acid (ja) could be an integral part of a general signal transduction system regulating inducible defense genes in plants. it was reported that treatment with an elicitor (n-acetylchitoheptaose) induced production of phytoalexin in suspension-cultured rice (oryza sativa l.) cells. in this study, the role of ja in the induction of phytoalexin production by n-acetylchitoheptaose was investigated. exogenously applied ([plus or minus])-ja (10-4 m) clearly induced t ...199612226190
isolation of a thiamine-binding protein from rice germ and distribution of similar proteins.a thiamine-binding protein was purified from rice germ (oryza sativa l.) by extraction, salting-out with ammonium sulfate, and column chromatography. from the results of molecular mass, kd and bmax values for thiamine-binding, binding specificity for thiamine phosphates and analog, the protein was suggested to be identical to the thiamine-binding protein in rice bran. the thiamine-binding protein w as more efficiently purified from rice germ than from rice bran. the protein was rich in glutamic ...199627299548
additive and antagonistic effects of ozone and salinity on the growth, ion contents and gas exchange of five varieties of rice (oryza sativa l.).five varieties of rice (oryza sativa l.) of varying salinity resistance were grown in non-saline and in saline conditions, with and without a repeated exposure to ozone at a concentration of 83 nmol mol(-1) giving an aot40 (cumulative exposure above 40 nmol mol(-1)) of 3600 nmol mol(-1) h. salinity caused a substantial reduction in shoot and root dry weight in all varieties, but the effect on root growth was proportionately less than on shoot growth. ozone reduced root dry weight but the treatme ...199615091377
expression of a late embryogenesis abundant protein gene, hva1, from barley confers tolerance to water deficit and salt stress in transgenic rice.a late embryogenesis abundant (lea) protein gene, hva1, from barley (hordeum vulgare l.) was introduced into rice suspension cells using the biolistic-mediated transformation method, and a large number of independent transgenic rice (oryza sativa l.) plants were generated. expression of the barley hva1 gene regulated by the rice actin 1 gene promoter led to high-level, constitutive accumulation of the hva1 protein in both leaves and roots of transgenic rice plants. second-generation transgenic r ...199612226181
coordinated regulation of the genes participating in starch biosynthesis by the rice floury-2 locus.the recessive floury-2 (flo-2) locus of rice (oryza sativa l.), which is located on chromosome 4, causes a strong reduction in expression of the gene encoding an isoform of branching enzyme rbe1 in immature seeds 10 d after flowering. mapping of the rbe1 gene demonstrated the localization on rice chromosome 6, suggesting that the wild-type floury-2 (flo-2) gene regulates rbe1 gene expression in trans. however, reduced expression of the genes encoding some other starch-synthesizing enzymes, inclu ...199612226172
novel dna probes capable of discriminating indica and japonica rice cultivars.we obtained two dna clones, g93 (1.6kb) and g318 (1.7kb) from indica rice (oryza sativa l.) cultivar culture 340. southern hybridization analysis indicated that both dna probes hybridized with dna of indica cultivars but not with japonica cultivars. some javanica cultivars dnas did not hybridize with these probes. nucleotide sequence (400bp) of a part of g93 showed a 65.8% g + c content. these novel dna probes can be used for the study of evolutional fingerprinting of rice cultivars.19968988367
genomic structure of the rice aldolase isozyme c-1 gene and its regulation through a ca 2+ -mediated protein kinase-phosphatase pathway.complementary and genomic dna clones coding for aldolase c-1, the fourth-type isozyme of aldolase in rice oryza sativa l., have been characterized. the organization of the gene is quite similar to those encoding rice aldolase c-a and a maize cytoplasmic-type aldolase, in that introns are located in the same position. amino acid sequences are highly conserved among cytoplasmic aldolases in plants. expression of the gene in rice callus is activated by a protein phosphatase inhibitor okadaic acid, ...19968616263
maturation and translation mechanisms involved in the expression of a myb gene of rice.we have isolated two overlapping cdnas coding for a myb-related protein expressed in aerobic and anaerobic rice (oryza sativa) roots and coleoptiles. analysis of their sequences reveals some peculiar features, suggesting the presence of post-transcriptional regulation events: an upstream orf, two unspliced introns and a putative leucine zipper in the orf coded by the unspliced rna. transient expression in protoplasts indicates that the upstream orf inhibits expression of a downstream coding sequ ...19979426621
fructose 1,6-bisphosphate aldolase activity in leaves of a rice mutant selected for enhanced lysine.unknown proteins isolated from mutant tissues of rice (oryza sativa l.) recovered from inhibitor selections were subsequently peptide microsequenced. database searches putatively identified one peptide as fructose 1,6-bisphosphate aldolase (ec 4.1.2.13). tissues of mutant rice, pi564784, and wild type (cv calrose 76) tissues were evaluated for aldolase activity. total enzyme activities were slightly lower in the mutant than the control but the differences were not significant. although the mutan ...19979419899
cloning and expression of five myb-related genes from rice seed.three elements in the promoter of rice glutelin genes are important for their endosperm specific expression. one of these, an aaca motif, has been shown to be a negative regulator in non-seed tissues and has a similarity to the barley gibberellin responsive element recognized by myb-like dna binding proteins. a cdna library constructed from immature rice seed was screened using two types of myb gene probes to isolate cdna clones representing genes encoding myb-like dna binding proteins that may ...19979370307
synergistic enhancement of the postthaw growth of cryopreserved rice cells by oxygenated perfluorocarbon and pluronic f-68the beneficial effects were assessed of supplementing culture medium with oxygenated perfluorocarbon, both alone and in combination with 0.01 (w/v) pluronic f-68, on the postthaw viability, following cryopreservation, of suspension cultured cells of the japonica rice, oryza sativa cv. taipei 309. the mean viability, as assessed by triphenyl tetrazolium chloride reduction, of cells at 4 days after thawing was increased 20% over control by oxygenated perfluorodecalin (p < 0.05) in 100-ml glass jar ...19979367608
isolation and characterization of matrix associated region dna fragments in rice (oryza sativa l.).to investigate the interactions between chromosomal dna and nuclear matrices in higher plants, matrix associated regions (mars) of rice (oryza sativa l.) dnas were cloned. first, we prepared nuclear matrices from isolated nuclei by digesting them with ecori and then extracting with 2 m nacl. about 6% of the total dna remained in the nuclear matrices after this digestion and extraction. the residual dna fragments in the nuclear matrices were cloned. some of the cloned dna fragments showed binding ...19979360323
microsatellite marker development, mapping and applications in rice genetics and breeding.microsatellites are simple, tandemly repeated di- to tetra-nucleotide sequence motifs flanked by unique sequences. they are valuable as genetic markers because they are co-dominant, detect high levels of allelic diversity, and are easily and economically assayed by the polymerase chain reaction (pcr). results from screening a rice genomic library suggest that there are an estimated 5700-10,000 microsatellites in rice, with the relative frequency of different repeats decreasing with increasing si ...19979291963
alien introgression in rice.rice (oryza sativa l.) productivity is affected by several biotic and abiotic stresses. the genetic variability for some of these stresses is limited in the cultivated rice germplasm. moreover, changes in insect biotypes and disease races are a continuing threat to increased rice production. there is thus an urgent need to broaden the rice gene pool by introgressing genes for such traits from diverse sources. the wild species of oryza representing aa, bb, cc, bbcc, ccdd, ee, ff, gg and hhjj geno ...19979291958
rice lipid transfer protein (ltp) genes belong to a complex multigene family and are differentially regulated.several cdna clones encoding three different lipid transfer proteins (ltps) have been isolated from rice (oryza sativa l.) in order to analyse the complexity, the evolution and the expression of the ltp gene family. the mature proteins deduced from three clones exhibited a molecular mass of 9 kda, in agreement with the molecular mass of other ltps from plants. the clones were shown to be homologous in the coding region, while the 3' non-coding regions diverged strongly between the clones. the oc ...19979305762
varietal differences in protein phosphorylation during cold treatment of rice leaves.the effects of cold stress on protein phosphorylation in leaves of rice (oryza sativa) seedlings were investigated. two-week-old rice seedlings were exposed to low temperature (5 degrees) for 6 hr at a relative humidity of 100%. the leaf protein extracts were phosphorylated in vitro. cold stress stimulated the phosphorylation of a 60 kda protein in the cold-sensitive rice variety, ir36. in the cold-tolerant rice variety, kitaibuki, this protein had already been phosphorylated. for greater clarif ...19979237396
phytoalexin production elicited by exogenously applied jasmonic acid in rice leaves (oryza sativa l.) is under the control of cytokinins and ascorbic acid.jasmonic acid (ja) has been shown to be a signaling compound which elicits the production of secondary metabolites including phytoalexins in plants. it has been shown that the phytoalexin production is elicited by exogenously applied ja in rice leaves. we now show that this phytoalexin production by exogenously applied ja is significantly counteracted by cytokinins, kinetin and zeatin. kinetin and zeatin also inhibit the induction of naringenin-7-o-methyltransferase (a key enzyme in rice phytoal ...19979257690
a reversibly glycosylated polypeptide (rgp1) possibly involved in plant cell wall synthesis: purification, gene cloning, and trans-golgi localization.we purified from pea (pisum sativum) tissue an approximately 40 kda reversibly glycosylated polypeptide (rgp1) that can be glycosylated by udp-glc, udp-xyl, or udp-gal, and isolated a cdna encoding it, apparently derived from a single-copy gene (rgp1). its predicted translation product has 364 aminoacyl residues and molecular mass of 41.5 kda. rgp1 appears to be a membrane-peripheral protein. immunogold labeling localizes it specifically to trans-golgi dictyosomal cisternae. along with other evi ...19979207152
differential induction of pyruvate decarboxylase subunits and transcripts in anoxic rice seedlings.in 2-d-old rice (oryza sativa l.) seedlings subjected to anoxic stress, pyruvate decarboxylase (pdc) activity increased 9-fold during a 168-h period. a polyclonal pdc antiserum that recognized alpha- and beta-subunits was used to quantify pdc protein by an enzyme-linked immunosorbant assay and showed a 5.6-fold increase, suggesting that the anoxically induced enzyme has a higher specific activity than the pdc isoform present under normoxia. immunoblot analysis showed that levels of both pdc subu ...19979232881
involvement of soluble proteinous factors in auxin-induced modulation of p-type atpase in rice (oryza sativa l.) seedlings.the marked difference in auxin sensitivity between plant roots and shoots was studied in terms of auxin-induced stimulation of membrane p-type atpase. the results suggest the existence in rice seedlings of, at least, two isoforms of soluble proteinous factors (spf), spf(i) and spf(ii), which are involved in the stimulatory action of auxin on the enzyme. it also is indicated that spf(i) which mediates the auxin effect in low hormone concentration range (10(-10)-10(-7) m iaa) is the dominant isofo ...19979202160
a group 3 lea cdna of rice, responsive to abscisic acid, but not to jasmonic acid, shows variety-specific differences in salt stress response.a cdna clone oslea3, encoding a group 3 late-embryogenesis abundant (lea) protein was isolated from roots of rice seedlings (oryza sativa l.). the encoded oslea3 protein has previously been found to accumulate to higher levels in roots of two salt-tolerant compared to a salt-sensitive rice variety in response to abscisic acid (aba) [moons et al., 1995. plant physiol. 107, 177-186]. the oslea3 protein (mr 20.5, pi 6.5) characteristically contains ten imperfect 11-mer amino acid repeats. exogenous ...19979218720
does decrease in ribulose-1,5-bisphosphate carboxylase by antisense rbcs lead to a higher n-use efficiency of photosynthesis under conditions of saturating co2 and light in rice plants?rice (oryza sativa l.) plants with decreased ribulose-1,5-bisphosphate carboxylase (rubisco) were obtained by transformation with the rice rbcs antisense gene under the control of the rice rbcs promoter. the primary transformants were screened for the rubisco to leaf n ratio, and the transformant with 65% wild-type rubisco was selected as a plant set with optimal rubisco content at saturating co2 partial pressures for photosynthesis under conditions of high irradiance and 25[deg]c. this optimal ...199712223722
expression of arginine decarboxylase in seedlings of indica rice (oryza sativa l.) cultivars as affected by salinity stress.the effect of salinity stress on the activity of arginine decarboxylase (adc, ec 4.1.1.19), the first enzyme in biosynthesis of polyamines (pa) from arginine, as well as its transcript level has been compared in salt-sensitive (m-1-48) and salt-tolerant (pokkali) rice cultivars. treatment of 72 h grown seedlings either with increasing concentrations of nacl or with 150 mm nacl for different time periods, showed a gradual increase of activity in pokkali. in m-1-48 an immediate increase followed b ...19979225858
comparative evaluation of within-cultivar variation of rice (oryza sativa l.) using microsatellite and rflp markers.the objective of this study was to determine an efficient way of detecting within-cultivar variation in rice varieties obtained from national and international germplasm collections. seventy-one rice cultivars were evaluated for within-cultivar variation using a combination of phenotypic, rflp, and microsatellite or simple sequence length polymorphism (sslp). variation between individuals within and accession and between duplicate accessions within a cultivar was detected even in cultivars that ...19979202415
transgenic rice (oryza sativa) endosperm expressing daffodil (narcissus pseudonarcissus) phytoene synthase accumulates phytoene, a key intermediate of provitamin a biosynthesis.rice (oryza sativa l.), the major food staple for more than two billion people, contains neither beta-carotene (provitamin a) nor c40 carotenoid precursors thereof in its endosperm. to improve the nutritional value of rice, genetic engineering was chosen as a means to introduce the ability to make beta-carotene into rice endosperm tissue. investigation of the biochemical properties of immature rice endosperm using [14c]-labelled substrates revealed the presence of geranyl geranyl diphosphate, th ...19979193076
transient expression of multiple genes in salinity-stressed young seedlings of rice (oryza sativa l.) cv. bura rata.to date only about 15 abundantly expressed osmoresponsive genes/proteins have been described in rice cultivars. using in vivo radiolabeling followed by two-dimensional electrophoresis and autoradiography, a record number of at least 35 salinity stress-induced polypeptides (14-90 kda) and 17 salt stress-repressed polypeptides were detected in a halotolerant indica rice cultivar bura rata. these include > 20 hitherto unreported rice polypeptides that exhibited a low abundance, short-term expressio ...19979168910
activity and distribution of methane-oxidizing bacteria in flooded rice soil microcosms and in rice plants (oryza sativa).the activity and distribution of ch(inf4)-oxidizing bacteria (mob) in flooded rice (oryza sativa) soil microcosms was investigated. ch(inf4) oxidation was shown to occur in undisturbed microcosms by using (sup14)ch(inf4), and model calculations indicated that almost 90% of the oxidation measured had taken place at a depth where only roots could provide the o(inf2) necessary. slurry from soil planted with rice had an apparent k(infm) for ch(inf4) of 4 (mu)m and a v(infmax) of 0.1 (mu)mol g (dry w ...199716535562
expansins and internodal growth of deepwater rice.the distribution and activity of the cell wall-loosening protein expansin is correlated with internodal growth in deepwater rice (oryza sativa l.). acid-induced extension of native cell walls and reconstituted extension of boiled cell walls were confined to the growing region of the internode, i.e. to the intercalary meristem (im) and the elongation zone. immunolocalization by tissue printing and immunoblot analysis, using antibody against cucumber expansin 29 as a probe, confirmed that rice exp ...199712223665
genetics of hybrid sterility and hybrid breakdown in an intersubspecific rice (oryza sativa l.) population.f1 hybrid sterility and "hybrid breakdown" of f2 and later generations in rice (oryza sativa l.) are common and genetically complicated. we used a restriction fragment length polymorphism linkage map and f4 progeny testing to investigate hybrid sterility and hybrid breakdown in a cross between "widely compatible" o. sativa ssp. japonica cultivar lemont from the southern u.s. and ssp. indica cultivar teqing from china. our results implicate different genetic mechanisms in hybrid sterility and hyb ...19979093864
phototropism of rice (oryza sativa l.) coleoptiles: fluence-response relationships, kinetics and photogravitropic equilibrium.phototropism of rice (oryza sativa l.) coleoptiles induced by unilateral blue light was characterized using red-light-grown seedlings. phototropic fluence-response relationships, investigated mainly with submerged coleoptiles, revealed three response types previously identified in oat and maize coleoptiles: two pulse-induced positive phototropisms and a phototropism that depended on stimulation time. the effective ranges of fluences and fluence rates were comparable to those reported for maize. ...199711541281
plant regeneration of indica rice (oryza sativa) cultivars from mature embryo-derived calli.plant regeneration from seven-week-old callus cultures derived from mature embryos of several indica rice cultivars was achieved with frequencies of morphogenic calli from 10 to 47%. three media were tested both for callogenesis and plant regeneration. for 3 of the 7 genotypes examined, the best combination of media for plant regeneration was murashige & skoog basal medium: msc (callogenesis) and msr (regeneration). the rates of callogenesis were not related to the capacity for plant regeneratio ...19979404510
rapid reconstitution of tonoplast h(+)-translocating pyrophosphatase from cultured rice cells into liposomes.we report the rapid and functional reconstitution of h(+)-pyrophosphatase (h(+)-ppase) from the tonoplast of cultured rice (oryza sativa l.) cells to proteoliposomes. the chaps-solubilized h(+)-ppase was incorporated into liposomes by gel-filtration. both the activities of ppi-hydrolysis and h(+)-pumping were influenced by the lipid-protein ratio and cholesterol.19979150610
phosphorylation of the c2 subunit of the proteasome in rice (oryza sativa l.).proteasomes function mainly in the atp-dependent degradation of proteins that have been conjugated with ubiquitin. to demonstrate the phosphorylation of proteasomes in plants, we conducted an enzymatic dephosphorylation experiment with a crude extract of rice cultured cells. the results indicated that the c2 subunit of the 20s proteasome is phosphorylated in vivo in cultured cells. an in-gel kinase assay and analysis of phospho-amino acids revealed that the c2 subunit is phosphorylated by a 40-k ...19979091324
chromosomal regions associated with segregation distortion of molecular markers in f2, backcross, doubled haploid, and recombinant inbred populations in rice (oryza sativa l.).chromosomal regions associated with marker segregation distortion in rice were compared based on six molecular linkage maps. mapping populations were derived from one interspecific backcross and five inter-subspecific (indica/japonica) crosses, including two f2 populations, two doubled haploid (dh) populations, and one recombinant inbred (ri) population. mapping data for each population consisted of 129-629 markers. segregation distortion was determined based on chi-square analysis (p < 0.01) an ...19979065686
purification and characterization of a (1-->3)-beta-d-glucan endohydrolase from rice (oryza sativa) bran.a (1-->3)-beta-glucanase with an apparent m(r) of 29,000 and an isoelectric point of 4.0 has been purified 2000-fold from extracts of rice bran, using fractional precipitation with ammonium sulfate, anion exchange chromatography, size-exclusion chromatography, chromatofocussing, and hydrophobic interaction chromatography. the enzyme can be classified with the ec 3.2.1.39 group, because it releases laminarabiose and higher laminara-oligosaccharides from linear (1-->3)-beta-d-glucans with an actio ...19979076936
differential ammonia-elicited changes of cytosolic ph in root hair cells of rice and maize as monitored by 2[prime],7[prime]-bis-(2-carboxyethyl)-5 (and -6)-carboxyfluorescein-fluorescence ratio.intact hair cells of young rice (oryza sativa l.) and maize roots (zea mays l.), grown without external nitrogen, were specifically loaded with 2[prime],7[prime]-bis-(2-carboxyethyl)-5 (and -6)-carboxyfluorescein acetoxymethyl ester to monitor fluorescence ratio cytosolic ph changes in response to external ammonia (nh4+/nh3) application. in neutral media, cytosolic ph of root hairs was 7.15 [plus or minus] 0.13 (o. sativa) and 7.08 [plus or minus] 0.11 (z. mays). application of 2 mm ammonia at e ...199712223619
epistasis for three grain yield components in rice (oryza sativa l.).the genetic basis for three grain yield components of rice, 1000 kernel weight (kw), grain number per panicle (gn), and grain weight per panicle (gwp), was investigated using restriction fragment length polymorphism markers and f4 progency testing from a cross between rice subspecies japonica (cultivar lemont from usa) and indica (cv. tequing from china). following identification of 19 qtl affecting these traits, we investigated the role of epistasis in genetic control of these phenotypes. among ...19979071598
characterization of a maize beta-amylase cdna clone and its expression during seed germination.a maize (zea mays l.) cdna clone (pzmb2) encoding beta-amylase was isolated from a cdna library prepared from the aleurone rna of germinating kernels. the cdna encodes a predicted product of 488 amino acids with significant similarity to known beta-amylases from barley (hordeum vulgare), rye (secale cereale), and rice (oryza sativa). glycine-rich repeats found in the carboxyl terminus of the endosperm-specific beta-amylase of barley and rye are absent from the maize gene product. the n-terminal ...19979046591
phytoalexin production by amino acid conjugates of jasmonic acid through induction of naringenin-7-o-methyltransferase, a key enzyme on phytoalexin biosynthesis in rice (oryza sativa l.).amino acid conjugates of jasmonic acid are found to elicit production of the flavonoid phytoalexin, sakuranetin in rice leaves. the elicitation is shown to arise from induction of naringenin 7-o-methyltransferase, a key enzyme of sakuranetin biosynthesis. the (-)-phenylalanine conjugate, one of the active compounds, is characterized by high activity for both sakuranetin and enzyme induction and low phytotoxicity against rice growth. both (+)-enantiomers of the conjugates and free amino acids do ...19979013895
effects of ethylene and gibberellins on the elongation of rice seedlings (oryza sativa l.).three-day-old rice seedlings treated with ethylene showed elongation of the 2nd and 3rd leaves. this ethylene-stimulated elongation was not observed in the presence of uniconazole-p or prohexadione, both gibberellin (ga) biosynthesis inhibitors, suggesting that ga was involved in the response. an analysis of endogenous gas by gc-ms revealed that the ga1 level was reduced in the 3rd leaf in response to ethylene. dose-response experiments showed that the responsiveness to ga1 was enhanced by ethyl ...199728862568
semi quantification of gibberellins in the anthers of thermosensitive genetic male sterile rice (oryza sativa l. cv. pl12).the levels of endogenous gas in the anthers of rice (oryza sativa l., cv. reimei (normal)) and in those of sterile and fertile plants of a thermosensitive genetic male sterile line (norin pl12; derived from reimei) were measured by enzyme-linked immunosorbent assay (elisa). high levels of ga4/7 were detected in the anthers of reimei (normal fertility) and fertile (growing under fertile conditions) pl 12, while such levels were markedly reduced with increased sterility in pl12. the anthers of the ...199727393172
identifying different types of de-differentiated microspores from indica-japonica f(1) hybrids with subspecies-differentiating rflp probes in rice.the indica, japonica and intermediary types of de-differentiated microspores from indica-japonica f(1) hybrids were identified with 11 subspecies-differentiating relp probes in rice (oryza sativa l.). the results showed that the distribution of indica, japonica and intermediary types of de-differentiated microspores could be easily detected in a simple and quick way using the rflp method. moreover, the microspores from the same f(1) hybrid but inoculated onto different media, or microspores from ...199719352742
characteristics of genetic variation in the progenies of protoplast-derived plants of rice, oryza sativa cv nipponbare.genetic variation in protoplast-derived rice (oryza sativa l.) plants was characterized using first and second generation selfed progenies. a total of 133 regenerated plants were obtained from ten protoplasts of the japonica rice cultivar nipponbare. sixty two regenerated plants which set enough seeds for the subsequent field tests at the next generation and were derived from five protoplasts were selected, and their selfed seeds were used as the first selfed-seed progeny (pt(1) generation). fif ...199719352738
ultraviolet b-sensitive rice cultivar deficient in cyclobutyl pyrimidine dimer repair.repair of cyclobutyl pyrimidine dimers (cpds) in dna is essential in most organisms to prevent biological damage by ultraviolet (uv) light. in higher plants tested thus far, uv-sensitive strains had higher initial damage levels or deficient repair of nondimer dna lesions but normal cpd repair. this suggested that cpds might not be important for biological lesions. the photosynthetic apparatus has also been proposed as a critical target. we have analyzed cpd induction and repair in the uv-sensiti ...199712223592
an abscisic-acid- and salt-stress-responsive rice cdna from a novel plant gene family.a novel cdna clone osr40cl, encoding a abscisic acid (aba)-responsive 40-kda protein previously associated with salt tolerance (moons et al. '1995' plant physiol 107: 177-186), was isolated from roots of rice seedlings (oryza sativa l.). exogenously applied aba and salt shock induced a marked increase of the osr40cl transcript level in roots of seedlings whereas constant osr40cl mrna levels were found in the shoot. the root-specific salinity-induced osr40cl mrna accumulation was rapid and gradua ...19979265787
cell wall (1-->3)- and (1-->3, 1-->4)-beta-glucans during early grain development in rice (oryza sativa l.).immunogold labeling was used to study the distribution of (1-->3)-beta-glucans and (1-->3, 1-->4)-beta-glucans in the rice grain during cellularization of the endosperm. at approximately 3-5 d after pollination the syncytial endosperm is converted into a cellular tissue by three developmentally distinct types of wall. the initial free-growing anticlinal walls, which compartmentalize the syncytium into open-ended alveoli, are formed in the absence of mitosis and phragmoplasts. this stage is follo ...19979265785
molecular cloning and characterization of a cdna for plastidic copper/zinc-superoxide dismutase in rice (oryza sativa l.).a cdna encoding plastidic cu/zn-sod was isolated from rice. the deduced amino acid sequence included a transit peptide in the amino-terminal residues and showed a high similarity to those of plastidic cu/zn-sods from other plants. the level of expression of this transcript was high in green leaves and differed from that of other rice sod mrnas in various tissues.19979057336
expression characteristics of os-acs1 and os-acs2, two members of the 1-aminocyclopropane-1-carboxylate synthase gene family in rice (oryza sativa l. cv. habiganj aman ii) during partial submergence.deepwater rice can grow in the regions of southeast asia that are flooded during the monsoon season because it has several adaptations allowing it to survive under flooded conditions. one such adaptation is the ability for rapid internode elongation upon partial submergence to maintain its foliage above the rising flood water levels. ethylene is considered to be the trigger of this growth response because deepwater conditions not only trap ethylene in submerged organs, but also enhance the activ ...19979037160
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 ...199711541059
physical and kinetic evidence for an association between sucrose-phosphate synthase and sucrose-phosphate phosphatase.the possible formation of a multienzyme complex between sucrose (suc)-phosphate synthase (sps) and suc-phosphate phosphatase (spp) was examined by measuring the rates of suc-6-phosphate (suc-6-p) synthesis and hydrolysis in mixing experiments with partially purified enzymes from spinach (spinacia oleracea) and rice (oryza sativa) leaves. the addition of spp to sps stimulated the rate of suc-6-p synthesis. sps inhibited the hydrolysis of exogenous suc-6-p by spp when added in the absence of its s ...199712223802
growth and n allocation in rice plants under co2 enrichment.the effects of co2 enrichment on growth and n allocation of rice (oryza sativa l.) were examined. the plants were grown hydroponically in growth chambers with a 14-h photoperiod (1000 [mu]mol quanta m-2 s-1) and a day/night temperature of 25/20[deg]c. from the 28th to 70th d after germination, the plants were exposed to two co2 partial pressures, namely 36 and 100 pa. the co2 enrichment increased the final biomass, but this was caused by a stimulation of the growth rate during the first week of ...199712223800
the effect of elevated partial pressures of co2 on the relationship between photosynthetic capacity and n content in rice leaves.the effects of growth co2 levels on the photosynthetic rates; the amounts of ribulose-1,5-bisphosphate carboxylase (rubisco), chlorophyll (chl), and cytochrome f; sucrose phosphate synthase activity; and total n content were examined in young, fully expanded leaves of rice (oryza sativa l.). the plants were grown hydroponically under two co2 partial pressures of 36 and 100 pa at three n concentrations. the light-saturated photosynthesis at 36 pa co2 was lower in the plants grown in 100 pa co2 th ...199712223799
effects of osmoprotectants upon nacl stress in rice.plants accumulate a number of osmoprotective substances in response to nacl stress, one of them being proline (pro). while characterizing some of the changes in solute accumulation in nacl-stressed rice (oryza sativa l.), we identified several other potential osmoprotectants. one such substance, trehalose, begins to accumulate in small amounts in roots after 3 d. we performed a series of experiments to compare the effects of pro and trehalose on ion accumulation to determine whether the two chem ...199712223797
accelerated early growth of rice at elevated co2 (is it related to developmental changes in the shoot apex?).the influence of elevated co2 on the development of the shoot apex and on subsequent vegetative growth and grain yield was investigated using rice (oryza sativa l. cv jarrah) grown in flooded soil at either 350 or 700 [mu]l co2 l-1. at 8 d after planting (dap), elevated co2 increased the height and diameter of the apical dome and lengths of leaf primordia and tiller buds but had no effect on their numbers. by 16 dap, there were five tiller buds in the apex at 700 [mu]l co2 l-1 compared with only ...199712223789
structure, chromosomal location and expression of a rice gene encoding the microsome omega-3 fatty acid desaturase.the omega-3 fatty acid desaturases are membrane-bound enzymes catalyzing the conversion of linoleic acid to linolenic acid in lipids, and are located both in the microsome and plastid envelopes as two different isoforms. a cdna encoding the microsome omega-3 fatty acid desaturase (osfad3) and the corresponding genomic clone were isolated from rice (oryza sativa l.). the osfad3 gene was composed of 8 exons and 7 introns. a microsatellite was present in the second exon of the osfad3 gene, showing ...19979049269
expression, secretion, and processing of rice alpha-amylase in the yeast yarrowia lipolytica.the gene encoding rice alpha-amylase in oryza sativa was expressed in the yeast yarrowia lipolytica, which is a potential host system for heterologous protein expression. for efficient secretion, the strong and inducible xpr2 promoter was used in the construction of four kinds of expression vectors with the following configurations between the xpr2 promoter and terminator: 1) xpr2 prepro-region-rice alpha-amylase coding sequence, 2) rice alpha-amylase signal peptide-rice alpha-amylase coding seq ...19979054373
chloroplast dna variability in wild and cultivated rice (oryza spp.) revealed by polymorphic chloroplast simple sequence repeats.short mononucleotide repeats analogous to nuclear microsatellites or simple sequence repeats (ssrs) have been identified in chloroplast genomes. primers flanking mononucleotide repeats in the fully sequenced rice chloroplast genome have been used in conjunction with pcr to amplify genomic dna from 42 wild rice accessions. the amplification products exhibited length polymorphism, which allowed the levels of chloroplast variability detected to be quantified. seven primer pairs that amplified produ ...19979061917
differential expression of a cak (cdc2-activating kinase)-like protein kinase, cyclins and cdc2 genes from rice during the cell cycle and in response to gibberellin.progress through the eukaryotic cell cycle is regulated by cyclin-dependent cdc2 protein kinases. in rice (oryza sativa l), two cdc2 protein kinases, cdc2os-1 and cdc2os-2, and two cyclins, cycos1 and cycos2, have been described. in this study, we report on the cell-cycle phase-specific expression of these genes. using partially synchronized suspension cells from rice, we found that cdc2os-1 was expressed constitutively throughout the cell cycle. the cdc2os-2 transcript level was elevated in g1 ...19979076986
the root hair defective3 gene encodes an evolutionarily conserved protein with gtp-binding motifs and is required for regulated cell enlargement in arabidopsis.in plants, morphogenesis is largely determined by the orientation and extent of cell enlargement. to define the molecular mechanisms regulating plant cell enlargement, we have conducted a molecular genetic analysis of the root hair defective3 (rhd3) gene of arabidopsis thaliana. mutations affecting the rhd3 gene were found to alter cell size, but not cell number, in tissues throughout the plant. genetic and physiological analyses suggest that the rhd3 gene is not required for proper cell type sp ...19979087433
structure of the rice glutaredoxin (thioltransferase) gene.we have isolated the gene encoding a glutaredoxin in rice (oryza sativa l.) and determined the nucleotide (nt) sequence of about a 4.2 kb long. the cloned gene (grasc8) was found to contain four exons interrupted by three introns. the first exon begins the atg translation start codon and the four exons code for a protein composed of 112 amino acids. the tetrapeptide -cys-pro-phe-cys- [-cys-pro-phe(tyr)-cys-] which constitutes an active site of escherichia coli and mammalian glutaredoxins, was co ...19979099854
cloning and characterization of the osnramp family from oryza sativa, a new family of membrane proteins possibly implicated in the transport of metal ions.the mammalian nramp1 protein is an integral membrane protein expressed exclusively in macrophages, where it plays a critical role in the ability of these cells to destroy ingested microbes. the bactericidal mechanism of action of nramp1 remains unknown. we report the identification and characterization of cdna clones corresponding to three homologues of the mammalian nramp1 gene from the genome of oryza sativa, osnramp1, osnramp2, and osnramp3. these three genes encode a novel group of highly si ...19979154989
molecular characterization of a rab-related small gtp binding protein cdna from rice (oryza sativa l. ir-36).to study physiological roles of plant small gtp binding proteins, we isolated a cdna clone (orrab2) encoding the rab-related small gtp binding protein from rice (oryza sativa l. ir-36) by using human cdna rab2 as a probe. the deduced amino acid sequence of the orrab2 gene shared all the conserved regions, important for gtpase/gtp binding activities, with those of other small gtp binding proteins. orrab2 is a 1028 bp long cdna, encodes a 23.2 kda protein which shows 85.2% similarity on the amino ...19979163737
biochemical characteristics of a rice (oryza sativa l., ir36) g-protein alpha-subunit expressed in escherichia coli.a cdna encoding the alpha-subunit of the heterotrimeric g-protein in rice (rga1) was overexpressed in escherichia coli and then isolated by ni2+-nitrilotriacetic acid affinity chromatography. the molecular mass of rga1 bearing a his tag was approx. 49 kda. immunoblot analysis using anti-rga1 revealed that the rga1 protein is most abundant in seedling leaves and least abundant in mature roots. it exists at particularly high levels in the immature embryo after pellicle extrusion. in addition, the ...19979164867
purification and characterization of glutaredoxin (thioltransferase) from rice (oryza sativa l.).we purified and characterized glutaredoxin (thioltransferase), which catalyzes thiol/disulfide exchange reaction, for the first time in plants. the purification procedure employed an immunoabsorbent, antiglutaredoxin-sepharose. glutaredoxin was purified about 2,200-fold from rice bran and it appeared to be homogeneous on sds-page. maldi-tof mass spectrometry revealed that the protein has a molecular mass of 11,097.9 da. rice glutaredoxin consists of 105 amino acid residues, containing the tetrap ...19979192723
expression of a betaine aldehyde dehydrogenase gene in rice, a glycinebetaine nonaccumulator, and possible localization of its protein in peroxisomes.betaine aldehyde dehydrogenase (badh) catalyzes the last step in the plant biosynthetic pathway that leads to glycinebetaine. rice plants (oryza sativa l.), albeit considered a typical non-glycinebetaine accumulating species, have been found to express this enzyme at low levels. this observation evokes an interest in phylogenic evolution of the enzyme in the plant kingdom. it is reported here that rice plants possess the ability to take up exogenously added betaine aldehyde through the roots and ...19979193078
a large-insert (130 kbp) bacterial artificial chromosome library of the rice blast fungus magnaporthe grisea: genome analysis, contig assembly, and gene cloning.magnaporthe grisea (hebert) barr causes rice blast, one of the most devastating diseases of rice (oryza sativa) worldwide. this fungus is an ideal organism for studying a number of aspects of plant-pathogen interactions, including infection-related morphogenesis, avirulence, and pathogen evolution. to facilitate m. grisea genome analysis, physical mapping, and positional cloning, we have constructed a bacterial artificial chromosome (bac) library from the rice infecting strain 70-15. a new metho ...19979290247
molecular cloning and further characterization of a probable plant vacuolar sorting receptor.bp-80 is a type i integral membrane protein abundant in pea (pisum sativum) clathrin-coated vesicles (ccvs) that binds with high affinity to vacuole-targeting determinants containing asparagine-proline-isoleucine-arginine. here we present results from cdna cloning and studies of its intracellular localization. its sequence and sequences of homologs from arabidopsis, rice (oryza sativa), and maize (zea mays) define a novel family of proteins unique to plants that is highly conserved in both monoc ...19979306690
epigenetic transcriptional silencing and 5-azacytidine-mediated reactivation of a complex transgene in rice.despite a growing number of reports indicating non-mendelian inheritance of transgene expression in monocots, no detailed description of the structure and stability of the transgene exists for transformants generated by direct dna-transfer techniques, making the cause for these observations difficult to determine. in this paper we describe the complex organization of btt cryiiia and bar transgenes in rice (oryza sativa l.) that displayed aberrant segregation in r1 progeny. silencing rather than ...19979342860
structure and expression of two cdnas encoding s-adenosyl-l-methionine synthetase of rice (oryza sativa l.).two cdnas encoding rice (oryza sativa l.) s-adenosyl-l-methionine synthetase (sams) have been cloned, sequenced and identified. the deduced protein sequences share a high homology (90-94%) with those of other plant sams and are 60-62% identical to yeast, rat and human sams. the rice sams genes are differentially regulated in a tissue-specific manner and by a salt stress, while they are coordinately expressed during growth of the rice cell culture.19979375784
rice hemoglobins. gene cloning, analysis, and o2-binding kinetics of a recombinant protein synthesized in escherichia coli.although nonsymbiotic hemoglobins (hbs) are found in different tissues of dicots and monocots, very little is known about hb genes in monocots and the function of hbs in nonsymbiotic tissues. we report the cloning and analysis of two rice (oryza sativa l.) hb genes, hb1 and hb2, that code for plant hbs. rice hb1 and hb2 genes contain four exons and three introns, as with all of the known plant hb genes. at least three copies of the hb gene were detected in rice dna, and analysis of gene expressi ...19979390447
water permeability of plasma membranes of cultured rice, grape, and ch27 cells measured dielectrically.the capacitance of suspensions of cultured rice cells (oryza sativa l. ssp. japonica), grape cells (vitis sp.), and ch27 cells originated from murine b-cell lymphoma was measured in the frequency range of 0.2 to 10 mhz. the relationship between the increase in capacitance caused by the presence of cells at 0.4 mhz, delta c, and the cell density was linear. measurement of capacitance was useful in measurement of transitional changes in cell volume under external osmotic stress when sucrose was ad ...19979404061
cdna cloning and tissue specific expression of a gene for sucrose transporter from rice (oryza sativa l.).we describe the cloning and expression analysis of a sucrose transporter cdna from a monocot (the rice plant, oryza sativa l.). the cdna clone (ossut1) encoded an open reading frame of 1,611 bp (537 amino acids) and showed 76.8 to 79.7% similarity at the amino acid level to other sucrose transporters of dicot species. the predicted membrane topology of ossut1 protein is made up of 12 transmembrane helices which is consistent with most of the mono- and disaccharide transporters previously identif ...19979522469
[the use of a multimix as a dietary supplement: study in rats].a multimistura (mm)--sweet cassava (manihot esculenta crantz) leaf flour, wheat bran (tritium aestivum l.), egg shell powder, pumpkin (cucurbita spp) and sunflower (heliantus annus) seed flours--was added to a mixture of beans, 7% (phaseolus vulgaris) and rice, 3% (oryza sativa) and its effects, were assessed in weanling, male albino (wistar) rats (n = 60). animals were divided into 6 groups: groups 1, 2 and 3 were fed beans + rice + multimixture (b + r + mm), beans + rice (b + r) and 10% casein ...19979673680
jasmonate-inducible genes are activated in rice by pathogen attack without a concomitant increase in endogenous jasmonic acid levels.the possible role of the octadecanoid signaling pathway with jasmonic acid (ja) as the central component in defense-gene regulation of pathogen-attacked rice was studied. rice (oryza sativa l.) seedlings were treated with ja or inoculated with the rice blast fungus magnaporthe grisea (hebert) barr., and gene-expression patterns were compared between the two treatments. ja application induced the accumulation of a number of pathogenesis-related (pr) gene products at the mrna and protein levels, b ...199712223690
differential accumulation of salicylic acid and salicylic acid-sensitive catalase in different rice tissues.we previously proposed that salicylic acid (sa)-sensitive catalases serve as biological targets of sa in plant defense responses. to further examine the role of sa-sensitive catalases, we have analyzed the relationship between sa levels and sa sensitivity of catalases in different rice (oryza sativa) tissues. we show here that, whereas rice shoots contain extremely high levels of free sa, as previously reported (i. raskin, h. skubatz, w. tang, b.j.d. meeuse [1990] ann bot 66: 369-373; p. silverm ...199712223699
gene-expression patterns and levels of jasmonic acid in rice treated with the resistance inducer 2,6-dichloroisonicotinic acid.acquired disease resistance can be induced in rice (oryza sativa) by a number of synthetic or natural compounds, but the molecular mechanisms behind the phenomenon are poorly understood. one of the synthetic inducers of resistance, 2,6-dichloroisonicotinic acid (ina), efficiently protected rice leaves from infection by the rice blast fungus magnaporthe grisea (hebert) barr. a comparison of gene-expression patterns in plants treated with ina versus plants inoculated with the compatible pathogen m ...199712223792
l-myo-lnositol 1-phosphate synthase from plant sources (characteristics of the chloroplastic and cytosolic enzymes).l-myo-inositol 1-phosphate synthase (ec 5.5.1.4) from cyanobacterial (spirulina platensis), algal (euglena gracilis), and higher plant (oryza sativa, vigna radiata) sources was purified to electrophoretic homogeneity, biochemically characterized, and compared. both chloroplastic and cytosolic forms of the enzyme were detected in e. gracilis, o. sativa, and v. radiata, whereas only the cytosolic form was detected in streptomycin-bleached or chloroplastic mutants of e. gracilis and in s. platensis ...199712223840
a synopsis of the occurrence and pathogenicity of phytophthora species in mainland china.to date, 26 species of phytophthora have been reported in mainland china but only 23 are accepted as good taxa. phytophthora nicotianae (p. parasitica) is the single most important species causing over 40 different plant diseases; p. boehmeriae is widespread attacking gossypium, boehmeria, citrus, broussonetia papyrifera and pterocarya stenoptera; p. "fragariae var. oryzo-bladis" is unique to mainland china causing blight of oryza sativa seedlings; p. megasperma sensu lato has been isolated from ...199716283113
a major quantitative trait locus for rice yellow mottle virus resistance maps to a cluster of blast resistance genes on chromosome 12.abstract two doubled-haploid rice populations, ir64/azucena and irat177/ apura, were used to identify markers linked to rice yellow mottle virus (rymv) resistance using core restriction fragment length polymorphism (rflp) maps. resistance was measured by mechanical inoculation of 19-day-old seedlings followed by assessment of virus content by enzyme-linked immunosorbent assay tests 15 days after inoculation. ir64/azucena and irat177/apura populations, 72 and 43 lines, respectively, were evaluate ...199718945025
the effects of a selection of alkaloids on the invertase activity of some higher plants.the effects of several alkaloids on the invertase activities of ricinus communis, solanum tuberosum, oryza sativa and carica papaya were studied. the following alkaloids: caffeine, berberine, strychnine, morphine, ethyl-narceine and nornicotine, have different inhibitory effects on invertase activity. kinetic studies of the alkaloid inhibition revealed that different alkaloids exhibited diverse types of inhibition of invertase. it was found that alkaloids form reversible complexes with invertase ...19979442928
expansins in deepwater rice internodes.cell walls of deepwater rice (oryza sativa l.) internodes undergo long-term extension (creep) when placed under tension in acidic buffers. this is indicative of the action of the cell wall-loosening protein expansin. wall extension had a ph optimum of around 4.0 and was abolished by boiling. acid-induced extension of boiled cell walls could be reconstituted by addition of salt-extracted rice or cucumber cell wall proteins. cucumber expansin antibody recognized a single protein band of 24.5-kd ap ...19979112771
characterization of the gene for delta1-pyrroline-5-carboxylate synthetase and correlation between the expression of the gene and salt tolerance in oryza sativa l.a cdna for delta1-pyrroline-5-carboxylate (p5c) synthetase (cosp5cs), an enzyme involved in the biosynthesis of proline, was isolated and characterized from a cdna library prepared from 14-day-old seedlings of oryza sativa cv. akibare. the deduced amino acid sequence of the p5cs protein (osp5cs) from o. sativa exhibited 74.2% and 75.5% homology to that of the p5cs from arabidopsis thaliana and vigna aconitifolia, respectively. northern blot analysis revealed that the gene for p5cs (osp5cs) was i ...19979106509
phytosulfokine-alpha, a sulfated pentapeptide, stimulates the proliferation of rice cells by means of specific high- and low-affinity binding sites.peptide growth factors were isolated from conditioned medium derived from rice (oryza sativa l.) suspension cultures and identified to be a sulfated pentapeptide [h-tyr(so3h)-ile-tyr(so3h)-thr-gln-oh] and its c-terminal-truncated tetrapeptide [h-tyr(so3h)-ile-tyr(so3h)-thr-oh]. these structures were identical to the phytosulfokines originally found in asparagus (asparagus officinalis l.) mesophyll cultures. the pentapeptide [phytosulfokine-alpha (psk-alpha)] very strongly stimulated colony forma ...19979371850
expression of snowdrop lectin (gna) in transgenic rice plants confers resistance to rice brown planthopper.snowdrop lectin (galanthus nivalis agglutinin; gna) has been shown previously to be toxic towards rice brown planthopper (nilaparvata lugens; bph) when administered in artificial diet. bph feeds by phloem abstraction, and causes 'hopper burn', as well as being an important virus vector. to evaluate the potential of the gna gene to confer resistance towards bph, transgenic rice (oryza sativa l.) plants were produced, containing the gna gene in constructs where its expression was driven by a phloe ...19989753773
proline suppresses rubisco activity in higher plants.seedlings of brassica juncea, sesbania sesban, and oryza sativa exposed to salt stress accumulated proline to levels as high as 4- to 20-fold over those of controls. because chloroplasts are the major site for synthesis of stress induced proline accumulation, in vitro studies were conducted to see how the over-accumulation of this solute influences the activity of the major chloroplastic enzyme ribulose 1,5-bis-phosphate carboxylase (rubisco) purified from the above plant species. surprisingly, ...19989826546
characterization of the rice pathogen-related protein rir1a and regulation of the corresponding gene.in rice (oryza sativa l.), local acquired resistance against pyricularia oryzae (cav.), the causal agent of rice blast, can be induced by a preinoculation with the non-host pathogen pseudomonas syringae pv. syringae. we have cloned a cdna (rir1a) and a closely related gene (rir1b) corresponding to transcripts that accumulate in leaf tissue upon inoculation with p. syringae pv. syringae. the cdna encodes a putative 107 amino acid protein, rir1a, that exhibits a putative signal peptide cleavage si ...19989747803
physical mapping of duplicated genomic regions of two chromosome ends in rice.two genomic regions duplicated in distal ends of the short arms of chromosomes 11 and 12 in rice (oryza sativa l.) were characterized by yac ordering with 46 genetic markers. physical maps covering most of the duplicated regions were generated. thirty-five markers, including 21 rice cdna clones, showed the duplicated loci arrayed strictly in the same order along the two specific genomic regions. regardless of their different genetic distances, the two duplicated segments may have a similar and m ...19989832535
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