Publications
| Title | Abstract | Year Filter | PMID(sorted ascending) Filter |
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| 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 |
| active retrotransposons are a common feature of grass genomes. | a large fraction of the genomes of grasses, members of the family graminae, is composed of retrotransposons. these elements resemble animal retroviruses in their structure and possess a life cycle similar to theirs that includes transcription, translation, and integration of daughter copies. we have investigated if retrotransposons are generally transcribed in the grasses and other plants, and whether the various families of elements are translationally and integrationally active in multiple gra ... | 2001 | 11244109 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| expression of a gibberellin 2-oxidase gene around the shoot apex is related to phase transition in rice. | a major catabolic pathway for gibberellin (ga) is initiated by 2beta-hydroxylation, a reaction catalyzed by ga 2-oxidase. we have isolated and characterized a cdna, designated oryza sativa ga 2-oxidase 1 (osga2ox1) from rice (oryza sativa l. cv nipponbare) that encodes a ga 2-oxidase. the encoded protein, produced by heterologous expression in escherichia coli, converted ga(1), ga(4), ga(9), ga(20), and ga(44) to the corresponding 2beta-hydroxylated products ga(8), ga(34), ga(51), ga(29), and ga ... | 2001 | 11244129 |
| 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 |
| protein phosphatase 2a: identification in oryza sativa of the gene encoding the regulatory a subunit. | a 2225 bp cdna, designated rpa1, was isolated from an oryza sativa cdna library. analysis revealed a 1761 bp coding sequence with 15 non-identical repeat units. the orf encoded the a regulatory subunit of protein phosphatase 2a (pp2a-a) as ascertained by complementation of the yeast tpd3 mutant defective in this gene. the corresponding genomic dna from a rice genome bac library revealed that the gene contains eleven introns. the rice genome contains only a single copy of this gene as judged by s ... | 2001 | 11247601 |
| 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 |
| identification of yac clones containing the mutable slender glume locus slg in rice (oryza sativa l.). | a mutable slender glume gene slg, which often reverts to the wild-type state, was induced by gamma-ray irradiation of seeds of the japonica rice cultivar 'gimbozu'. the final goal was to understand whether the slender glume mutation was associated with the insertion of a transposable element, utilizing map-based cloning techniques. the rflp (restriction fragment length polymorphism) analysis revealed that the slg locus was located between two rflp loci, xnpb33 and r1440, on chromosome 7 with rec ... | 2001 | 11269342 |
| 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 |
| futile transmembrane nh4(+) cycling: a cellular hypothesis to explain ammonium toxicity in plants. | most higher plants develop severe toxicity symptoms when grown on ammonium (nh(4)(+)) as the sole nitrogen source. recently, nh(4)(+) toxicity has been implicated as a cause of forest decline and even species extinction. although mechanisms underlying nh(4)(+) toxicity have been extensively sought, the primary events conferring it at the cellular level are not understood. using a high-precision positron tracing technique, we here present a cell-physiological characterization of nh(4)(+) acquisit ... | 0 | 11274450 |
| 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 |
| 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 |
| arginine decarboxylase transgene expression and analysis of environmental stress tolerance in transgenic rice. | arginine decarboxylase (adc) cdna from oat (avena sativa l.) was introduced into rice (oryza sativa l.) genome by an agrobacterium-mediated transformation method. expression of the adc transgene under the control of an aba-inducible promoter led to stress-induced upregulation of adc activity and polyamine accumulation in transgenic rice plants. second-generation (rl) transgenic rice plants showed an increase in biomass under salinity-stress conditions, as compared to the non-transformed control ... | 2001 | 11297783 |
| transgenic rice plants expressing the ferredoxin-like protein (ap1) from sweet pepper show enhanced resistance to xanthomonas oryzae pv. oryzae. | we used particle bombardment to cotransform mature seed-derived rice callus (oryza sativa l., ssp. japonica, cv. eyi 105) with plasmids containing the linked marker genes gusa and hpt, and the ap1 gene encoding an amphipathic protein previously shown to delay the hypersensitive response induced in non-host plants by the pathogen pseudomonas syringae pv. syringae (pss). thirty-two independent lines of transgenic rice plants were regenerated, and 27 of these lines carried all three transgenes as s ... | 2001 | 11297801 |
| 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 |
| azospirillum brasilense and azospirillum lipoferum hydrolyze conjugates of ga20 and metabolize the resultant aglycones to ga1 in seedlings of rice dwarf mutants. | azospirillum species are plant growth-promotive bacteria whose beneficial effects have been postulated to be partially due to production of phytohormones, including gibberellins (gas). in this work, azospirillum brasilense strain cd and azospirillum lipoferum strain usa 5b promoted sheath elongation growth of two single gene ga-deficient dwarf rice (oryza sativa) mutants, dy and dx, when the inoculated seedlings were supplied with [17,17-2h2]ga20-glucosyl ester or [17,17- 2h2]ga20-glucosyl ether ... | 2001 | 11299384 |
| identification and characterization of the gene encoding the mitochondrial elongation factor g in rice. | a plant nuclear gene coding for a mitochondrial elongation factor g (mef-g) was cloned from a cdna library and genomic library of rice (oryza sativa l.). this dna sequence predicts a 757-amino-acid protein exhibiting 79%, 55% and 49% homology to arabidopsis thaliana, saccharomyces cerevisiae and rat mef-g respectively, 53% homology to the elongation factor g in escherichia coli and 43% homology to soybean chloroplast elongation factor g. the deduced amino acid sequence contains the characteristi ... | 2000 | 11328648 |
| identification of defense-related rice genes by suppression subtractive hybridization and differential screening. | identification of host genes involved in defense responses is one of most critical steps leading to the elucidation of disease resistance mechanisms in plants. in this study, two different cloning strategies were employed to identify defense-related genes from a tropical japonica rice cultivar (oryza sativa cv. drew). with the use of bacterial colony arrays, differential screening of a blast fungus (pyricularia grisea)-induced rice cdna library led to the isolation of 22 distinct rice genes that ... | 2001 | 11332734 |
| 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 |
| toxicity-based criteria for the evaluation of textile wastewater treatment efficiency. | brazilian textile mills import wastewater treatment technologies, performances of which are generally evaluated only on a physicochemical basis. thus, a battery of bioassays was used to evaluate the performance of an ozonation system to treat textile effluents. comparative toxicological profiles for bacteria (vibrio fischeri), algae (scenedesmus subspicatus), daphnia (daphnia magna), fish (poecilia reticulata), and plants (soybean--glycine max, rice--oryza sativa, and wheat--triticum aestivum), ... | 2001 | 11345461 |
| in vivo evidence that ids3 from hordeum vulgare encodes a dioxygenase that converts 2'-deoxymugineic acid to mugineic acid in transgenic rice. | we proposed that an fe-deficiency-induced gene, ids3 (iron deficiency specific clone no. 3), from barley (hordeum vulgare l.) roots encodes a dioxygenase that catalyzes the hydroxylation step from 2'-deoxymugineic acid (dma) to mugineic acid (ma). to prove this hypothesis, we introduced the ids3 gene into rice (oryza sativa l.), which lacks ids3 homologues and secretes dma, but not ma. transgenic rice plants, carrying either ids3 cdna or a barley genomic dna fragment (20 kb) containing ids3, wer ... | 2001 | 11346963 |
| 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 |
| 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 |
| 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 |
| 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 |
| determination of phytochelatins by capillary zone electrophoresis with electrospray tandem mass spectrometry detection (cze-es ms/ms). | the coupling of capillary zone electrophoresis with electrospray mass spectrometry was optimized for the direct determination of phytochelatins (pcs) in extracts obtained from cells and plants that had been exposed to metal stress. gluthathione and phytochelatins belonging to the different families (gamma glu-cys)ngly (n-pc), (gamma glu-cys)nser, (gamma glu-cys)n beta ala and (gamma glu-cys)n were separated in an uncoated capillary at ph 4 using a 5 mm ammonium acetate buffer, and detected by el ... | 2001 | 11394303 |
| a new gypsy-type retrotransposon, rire7: preferential insertion into the tandem repeat sequence trsd in pericentromeric heterochromatin regions of rice chromosomes. | a portion of an insertion sequence present in a member of the rire3 family of retrotransposons in oryza sativa l. cv. ir36 was found to have an ltr sequence followed by a pbs sequence complementary to the 3'-end region of trnamet, indicative of another rice retrotransposon (named rire7). cloning and sequencing of pcr-amplified fragments that made up all parts of the rire7 sequence showed that rire7 is a gypsy-type retrotransposon with partial homology in the pol region to the rice gypsy-type ret ... | 2001 | 11405631 |
| designing herbicide formulation characteristics to maximize efficacy and minimize rice injury in paddy environments. | mathematical descriptors, coupled with experimental observations, are used to quantify differential uptake of an experimental herbicide in japonica and indica rice (oryza sativa, non-target) and barnyardgrass (echinochloa crus-galli, target). partitioning, degradation, plant uptake and metabolism are described using mass-balance conservation equations in the form of kinetic approximations. estimated environmental concentrations, governed by the pesticide formulation, are described using superimp ... | 2001 | 11407023 |
| 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 |
| 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 |
| 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 |
| isolation and characterization of a na+/h+ antiporter gene from the halophyte atriplex gmelini. | with a homologous gene region we successfully isolated a na+/h+ antiporter gene from a halophytic plant, atriplex gmelini, and named it agnhx1. the isolated cdna is 2607 bp in length and contains one open reading frame, which comprises 555 amino acid residues with a predicted molecular mass of 61.9 kda. the amino acid sequence of the agnhx1 gene showed more than 75% identity with those of the previously isolated nhx1 genes from glycophytes, arabidopsis thaliana and oryza sativa. the migration pa ... | 2001 | 11437248 |
| 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 |
| 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 |
| 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 |
| 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 |
| constancy of nitrogen turnover kinetics in the plant cell: insights into the integration of subcellular n fluxes. | compartmental analysis with 13n was used to determine cytosolic nitrate (no3-) pools, and their turnover rates, in roots of intact barley (hordeum vulgare l. cv klondike) seedlings. influx, efflux, flux to the vacuole and assimilation, and flux to the xylem, varied as much as 300-fold over a wide range of external no3- conditions. by contrast, the kinetic constant kc describing cytosolic no3- turnover varied by less than 4% from a mean value of 0.0407 min(-1). accordingly, cytosolic no3- pools v ... | 2001 | 11469581 |
| 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 |
| 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 |
| growth promotion of rice seedlings by allelopathic polysaccharide from welsh onion. | the underground portion of the welsh onion (allium fistulosum) was extracted and separated into seven fractions to purify allelopathic compounds that were found to promote the growth of rice seedlings (oryza sativa). the 80% (v/v) ethanol-insoluble fraction of the hot water extract showed the highest growth-promoting effect. purification by deae-cellulose chromatography gave four fractions, ad-1, 2, 3 and 4. ad-3 at 1000 ppm stimulated root and shoot growth by about 2.4 and 1.5 times over the re ... | 2001 | 11471727 |
| specific detection of bradyrhizobium and rhizobium strains colonizing rice (oryza sativa) roots by 16s-23s ribosomal dna intergenic spacer-targeted pcr. | in addition to forming symbiotic nodules on legumes, rhizobial strains are members of soil or rhizosphere communities or occur as endophytes, e.g., in rice. two rhizobial strains which have been isolated from root nodules of the aquatic legumes aeschynomene fluminensis (irbg271) and sesbania aculeata (irbg74) were previously found to promote rice growth. in addition to analyzing their phylogenetic positions, we assessed the suitability of the 16s-23s ribosomal dna (rdna) intergenic spacer (igs) ... | 2001 | 11472944 |
| 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 |
| 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 |
| two types of hkt transporters with different properties of na+ and k+ transport in oryza sativa. | it is thought that na+ and k+ homeostasis is crucial for salt-tolerance in plants. to better understand the na+ and k+ homeostasis in important crop rice (oryza sativa l.), a cdna homologous to the wheat hkt1 encoding k+-na+ symporter was isolated from japonica rice, cv nipponbare (ni-oshkt1). we also isolated two cdnas homologous to ni-oshkt1 from salt-tolerant indica rice, cv pokkali (po-oshkt1, po-oshkt2). the predicted amino acid sequence of ni-oshkt1 shares 100% identity with po-oshkt1 and ... | 2001 | 11489190 |
| characterization of rice anthranilate synthase alpha-subunit genes oasa1 and oasa2. tryptophan accumulation in transgenic rice expressing a feedback-insensitive mutant of oasa1. | anthranilate synthase (as) is a key enzyme in the synthesis of tryptophan (trp), indole-3-acetic acid, and indole alkaloids. two genes, oasa1 and oasa2, encoding as alpha-subunits were isolated from a monocotyledonous plant, rice (oryza sativa cv nipponbare), and were characterized. a phylogenetic tree of as alpha-subunits from various species revealed a close evolutionary relationship among oasa1 and arabidopsis asa2, ruta graveolens as alpha 2, and tobacco asa2, whereas oasa2, arabidopsis asa1 ... | 2001 | 11500548 |
| glucocorticoid-inducible gene expression in rice. | we have studied the use of a glucocorticoid receptor-based inducible gene expression system in the monocotyledonous model plant rice (oryza sativa l.). this system, originally developed by t. aoyama and n.-h. chua [(1997) plant j 11: 605-612], is based on the chimaeric transcriptional activator gvg, consisting of the yeast gal4 dna-binding domain, the vp16 activation domain and the glucocorticoid receptor domain. for application in rice, we designed an optimized binary vector series (pindex) and ... | 2001 | 11506359 |
| 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 |
| hydraulic conductivity of rice roots. | a pressure chamber and a root pressure probe technique have been used to measure hydraulic conductivities of rice roots (root lp(r) per m(2) of root surface area). young plants of two rice (oryza sativa l.) varieties (an upland variety, cv. azucena and a lowland variety, cv. ir64) were grown for 31-40 d in 12 h days with 500 micromol m(-2) s(-1) par and day/night temperatures of 27 degrees c and 22 degrees c. root lp(r) was measured under conditions of steady-state and transient water flow. diff ... | 2001 | 11520872 |
| molecular cloning and characterization of a novel jasmonate inducible pathogenesis-related class 10 protein gene, jiospr10, from rice (oryza sativa l.) seedling leaves. | a novel rice (oryza sativa l.) gene, homologous to a sorghum pathogenesis-related class 10 protein gene, was cloned from a cdna library prepared from 2-week-old jasmonic acid-treated rice seedling leaves, and named as jiospr10 (jasmonate inducible). jiospr10 encoded a 160-amino-acid polypeptide with a predicted molecular mass of 17,173.23 da and a pi of 5.84. jiospr10 was highly similar (77%) to the sorghum pr10 protein, but showed less than 55% similarity with other identified pr10s at the amin ... | 2001 | 11527396 |
| green and non-green callus induction from excised rice (oryza sativa) embryos: effects of exogenous plant growth regulators. | calli were induced either from excised rice embryos or from whole seeds in the presence of 1 to 5 mg l-1 naa. after 12 days of culture, calli were induced only from excised rice embryos. we found that excised embryos accumulated naa up to 6 times higher concentration than did whole seeds. in the presence of 1 to 5 mg l-1 naa and 2 to 10 mg l-1 kinetin, chlorophyllous calli were induced from excised rice embryos. chlorophyll contents in the callus tissue increased with increasing kinetin concentr ... | 1992 | 11537753 |
| function of silica bodies in the epidermal system of rice (oryza sativa l.): testing the window hypothesis. | silicon has been considered to be important for normal growth and development of the rice plant (oryza sativa l.). to investigate the physiological function of deposited silica in rice leaves, the hypothesis that silica bodies in the leaf epidermal system might act as a 'window' to facilitate the transmission of light to photosynthetic mesophyll tissue was tested. the silica content of leaves increased with supplied silicon and was closely correlated with the number of silica bodies per unit lea ... | 1996 | 11539362 |
| biological changes observed on rice and biological and genetic changes observed on tobacco [correction of tabacco] after space flight in the orbital station salyut-7 (biobloc iii experiment). | caryopses and isolated embryos from rice (oryza sativa l.) and tobacco seeds (nicotiana tabacum l. variety xanthi) were studied in the biobloc iii container aboard the soviet orbital space station salyut 7. the recovery from radiation damage under conditions of space flight was observed for rice caryopsis and embryos gamma irradiated (co 60, 50 grays) prior to launch. there was a large decrease in the percentage of germinating seeds from the tobacco strain tested when the seeds were exposed to h ... | 1984 | 11539650 |
| lazy gene (la) responsible for both an agravitropism of seedlings and lazy habit of tiller growth in rice (oryza sativa l.). | using an isogenic line of rice having lazy gene (la), we studied the correlation between the agravitropic response at the young seedling stage and the lazy habit (prostrate growth of tillers) at the more advanced stage of growth. in this study, it was found that both agravitropism and lazy habit were controlled by the single recessive la gene. that is, f2 segregants of kamenoo x lazy-kamenoo, which had an agravitropic response at their young seedling stage, showed a lazy habit of growth in the m ... | 1996 | 11539861 |
| photoperiod shift effects on yield characteristics of rice. | edible yield must be maximized for each crop species selected for inclusion in the controlled ecological life-support system (celss) proposed by nasa to support long-term manned space missions. in a greenhouse study aimed at increasing biomass partitioning to rice (oryza sativa l.) grain, plants of the high yielding semi-dwarf rice cultivar ai-nan-tsao were started in pots under 8-h photoperiods at a density of 212 plants m-2. after different periods of time under 8-h photoperiods, pots were swi ... | 2016 | 11540306 |
| suppression of gravitropic response of primary roots by submergence. | primary roots of six plant species were placed horizontally either in humid air or under water, and their growth and gravitropic responses were examined. in air, all the roots showed a normal gravitropic curvature. under water without aeration, roots of rice (oryza sativa l.), oat (avena sativa l.), azuki bean (vigna angularis ohwi et ohashi), and cress (lepidium sativum l.) curved downward at almost same rate as in air, whereas the curvature of roots of maize (zea mays l.) and pea (pisum sativu ... | 1996 | 11540722 |
| 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 |
| 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. ... | 1997 | 11541281 |
| rates of ethylene release, photosynthesis and transpiration of rice measured in closed-type chamber. | to obtain the basic data of gas exchange of rice (oryza sativa l. cv. nipponbare), rates of ethylene release, photosynthesis and transpiration of the rice plant were measured by using a closed-type chamber. each rate increased until the heading stage and thereafter decreased. ethylene release rate (e) gradually increased with day after seeding and rates of photosynthesis (p) and transpiration (t) did exponentially. at the heading stage, e, p and t were maximum and had values of about 2.0 mmol pl ... | 1996 | 11541585 |
| effects of submergence on development and gravitropism in the coleoptile of oryza sativa l. | caryopses of rice (oryza sativa l. cv. sasanishiki) were germinated in air or under water. in submerged seedlings a twofold increase in coleoptile growth rate and an inhibition of root growth was observed. the amount of starch in the amyloplasts of submerged coleoptiles was substantially reduced compared to the air-grown control plants and plastids had a proplastidic character. during the rapid elongation of coleoptiles under water, the osmotic concentration of the press sap remained constant, w ... | 1991 | 11541649 |
| 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 |
| growth regulation mechanisms in higher plants under microgravity conditions - changes in cell wall metabolism. | during space shuttle sts-95 mission, we cultivated seedlings of rice (oryza sativa l. cv. koshihikari and cv. tan-ginbozu) and arabidopsis (arabidopsis thaliana l. cv. columbia and cv. etr1-1) for 68.5, 91.5, and 136 hr on board, and then analyzed changes in the nature of their cell walls, growth, and morphogenesis under microgravity conditions. in space, elongation growth of both rice coleoptiles and arabidopsis hypocotyls was stimulated. also, the increase in the cell wall extensibility, espec ... | 2000 | 11543424 |
| 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 |
| 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 |
| hormonal changes in the grains of rice subjected to water stress during grain filling. | lodging-resistant rice (oryza sativa) cultivars usually show slow grain filling when nitrogen is applied in large amounts. this study investigated the possibility that a hormonal change may mediate the effect of water deficit that enhances whole plant senescence and speeds up grain filling. two rice cultivars showing high lodging resistance and slow grain filling were field grown and applied with either normal or high amount nitrogen (hn) at heading. well-watered and water-stressed (ws) treatmen ... | 2001 | 11553759 |
| [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 |
| [qtl analysis of anther length and ratio of stigma exsertion, two key traits of classification for cultivated rice (oryza sativa l.) and common wild rice (o. rufipogon griff.)]. | a genetic map including 120 rflp markers covering 1418.2 cm has been constructed using a bc1 population derived from a cross between common wild rice (oryza rufipogon griff.) from dongxiang, jiangxi province, china, and an elite indica variety guichao 2. the linkage orders and genetic distances of markers in this map are consistent with the map constructed by rice genome program of japan except the markers of short arm of chromosome 1. the qtls analysis of anther length and ratio of stigma exser ... | 2001 | 11554349 |
| [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 |
| beta-d-glycan synthases and the cesa gene family: lessons to be learned from the mixed-linkage (1-->3),(1-->4)beta-d-glucan synthase. | cellulose synthase genes (cesas) encode a broad range of processive glycosyltransferases that synthesize (1-->4)beta-d-glycosyl units. the proteins predicted to be encoded by these genes contain up to eight membrane-spanning domains and four 'u-motifs' with conserved aspartate residues and a qxxrw motif that are essential for substrate binding and catalysis. in higher plants, the domain structure includes two plant-specific regions, one that is relatively conserved and a second, so-called 'hyper ... | 2001 | 11554469 |
| 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 |
| 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 |
| 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 |
| brassinosteroid signaling in plants. | in animals and humans, steroid hormones (shs) regulate gene transcription via the binding of nuclear receptors. in addition, rapid nongenomic effects of steroids occur and appear to be mediated by plasma-membrane receptors. plants also use steroids as signaling molecules. these brassinosteroids (brs) show structural similarity to the shs of vertebrates and insects. plant mutants defective in brassinosteroid biosynthesis or perception exhibit dwarfism and reduced fertility, and reveal the need fo ... | 2001 | 11595541 |
| 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 |
| 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 |
| identification of a hepatic factor capable of supporting hepatitis c virus replication in a nonpermissive cell line. | although hepatitis c virus e2 protein can bind to human cells by interacting with a putative viral receptor, cd81, the interaction alone is not sufficient to establish permissiveness for hepatitis c virus infection. using an epstein-barr virus-based extrachromosomal replication system, we have screened through a human liver cdna library and successfully identified a cdna capable of supporting hepatitis c virus replication in an otherwise nonpermissive cell line. this cdna encodes a protein exhib ... | 2001 | 11602742 |
| 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 |
| 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 |
| endophytic colonization and in planta nitrogen fixation by a herbaspirillum sp. isolated from wild rice species. | nitrogen-fixing bacteria were isolated from the stems of wild and cultivated rice on a modified rennie medium. based on 16s ribosomal dna (rdna) sequences, the diazotrophic isolates were phylogenetically close to four genera: herbaspirillum, ideonella, enterobacter, and azospirillum. phenotypic properties and signature sequences of 16s rdna indicated that three isolates (b65, b501, and b512) belong to the herbaspirillum genus. to examine whether herbaspirillum sp. strain b501 isolated from wild ... | 2001 | 11679357 |
| 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 |
| 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 |
| seasonal changes of chlorophyll content in field-grown rice crops and their relationships with growth. | field experiments were conducted on the experimental farm of the taiwan agricultural research institute (tari) to examine seasonal changes in the amounts of chlorophylls in leaves and whole plants of rice (oryza sativa l. cv. tainung 67) grown in the first and the second crop seasons in 1998. chlorophyll (chl) differences between two crops and their relationships with growth were also investigated. the differences in climate conditions between the two crop seasons were quite phenomenal and led t ... | 2001 | 11699571 |
| diversity of arabidopsis genes encoding precursors for phytosulfokine, a peptide growth factor. | phytosulfokine-alpha (psk-alpha), a unique plant peptide growth factor, was originally isolated from conditioned medium of asparagus (asparagus officinalis) mesophyll cell cultures. psk-alpha has several biological activities including promoting plant cell proliferation. four genes that encode precursors of psk-alpha have been identified from arabidopsis. analysis of cdnas for two of these, atpsk2 and atpsk3, shows that both of these genes consist of two exons and one intron. the predicted precu ... | 2001 | 11706167 |
| significant accumulation of c(4)-specific pyruvate, orthophosphate dikinase in a c(3) plant, rice. | the c(4)-pdk gene encoding the c(4) enzyme pyruvate, orthophosphate dikinase (ppdk) of maize (zea mays cv golden cross bantam) was introduced into the c(3) plant, rice (oryza sativa cv kitaake). when the intact maize c(4)-pdk gene, containing its own promoter and terminator sequences and exon/intron structure, was introduced, the ppdk activity in the leaves of some transgenic lines was greatly increased, in one line reaching 40-fold over that of wild-type plants. in a homozygous line, the ppdk p ... | 2001 | 11706193 |
| 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 |
| 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 |
| 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 |
| 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 |
| characterization of a ca2+-dependent protein kinase from rice root: differential response to cold and regulation by abscisic acid. | the ca2+-dependent protein kinases (cdpks) and abscisic acid (aba) are known to be involved in low-temperature stress response. the focus of this study was to characterize the 45 kda protein kinase identified in the crude extract of rice (oryza sativa l.) seedling roots in response to cold (5 degrees c) stress. the activity of the 45 kda protein kinase decreased at low temperature as evident by an in-gel kinase assay using histone iii-s as a substrate. also, the ca2+-dependent activity of this p ... | 2001 | 11725971 |
| toward a cytological characterization of the rice genome. | rice (oryza sativa l.) will be the first major crop, as well as the first monocot plant species, to be completely sequenced. integration of dna sequence-based maps with cytological maps will be essential to fully characterize the rice genome. we have isolated a set of 24 chromosomal arm-specific bacterial artificial chromosomes to facilitate rice chromosome identification. a standardized rice karyotype was constructed using meiotic pachytene chromosomes of o. sativa spp. japonica rice var. nippo ... | 2001 | 11731505 |
| identification, purification, and characterization of a thermally stable lipase from rice bran. a new member of the (phospho) lipase family. | a thermally stable lipase (ec 3.1.1.3.) was first identified in rice (oryza sativa) bran, and the enzyme was purified to homogeneity using octyl-sepharose chromatography. the enzyme was purified to 7.6-fold with the final specific activity of 0.38 micromol min(-1) mg(-1) at 80 degrees c using [9,10-(3)h]triolein as a substrate. the purified enzyme was found to be a glycoprotein of 9.4 kd. enzyme showed a maximum activity at 80 degrees c and at ph 11.0. the protein was biologically active and ret ... | 2001 | 11743116 |
| role of root hairs and lateral roots in silicon uptake by rice. | the rice plant (oryza sativa l. cv oochikara) is known to be a si accumulator, but the mechanism responsible for the high uptake of si by the roots is not well understood. we investigated the role of root hairs and lateral roots in the si uptake using two mutants of rice, one defective in the formation of root hairs (rh2) and another in that of lateral roots (rm109). uptake experiments with nutrient solution during both a short term (up to 12 h) and relatively long term (26 d) showed that there ... | 2001 | 11743120 |
| a quinolone alkaloid with antioxidant activity from the aleurone layer of anthocyanin-pigmented rice. | the aleurone layer of oryza sativa cv. heugjinmi yielded a new quinolone alkaloid, 4-carbomethoxy-6-hydroxy-2-quinolone (1), showing moderate antioxidative activity in a 1,1-diphenyl-2-picrylhydrazyl free-radical scavenging assay. physical and spectroscopic evidence has determined the structure of the compound. | 2001 | 11754619 |
| effects of phenotyping environment on identification of quantitative trait loci for rice root morphology under anaerobic conditions. | in the rainfed lowlands, rice (oryza sativa l.) develops roots under anaerobic soil conditions with ponded water, prior to exposure to aerobic soil conditions and water stress. constitutive root system development in anaerobic soil conditions has been reported to have a positive effect on subsequent expression of adaptive root traits and water extraction during water stress. we examined effects of phenotyping environment on identification of quantitative trait loci (qtls) for constitutive root m ... | 2002 | 11756283 |
| osiaa1, an aux/iaa cdna from rice, and changes in its expression as influenced by auxin and light. | the aux/iaa class of genes are rapidly induced by exogenous auxins and have been characterized extensively from many dicot species like arabidopsis, glycine max and pisum sativum. we report here the isolation and characterization of rice (oryza sativa l. subsp. indica) osiaa1 cdna as a monocot member of the aux/iaa gene family. the predicted amino acid sequence of osiaa1 corresponds to a protein of ca. 26 kda, which harbors all four characteristic domains known to be conserved in aux/iaa protein ... | 2001 | 11759839 |
| iodate and iodide effects on iodine uptake and partitioning in rice (oryza sativa l.) grown in solution culture. | in the xinjiang province of western china, conventional methods of iodine (i) supplementation (i.e, goiter pills and iodinated salt) used to mitigate i deficiencies were ineffectual. however, the recent addition of kio3 to irrigation waters has proven effective. this study was conducted to determine the effects of i form and concentration on rice (oryza sativa l.) growth, i partitioning within the plant, and ultimately to assist in establishing guidelines for incorporating i into the human food ... | 1999 | 11762382 |
| analysis of genes expressed during rice-magnaporthe grisea interactions. | expressed sequence tag (est) analysis was applied to identify rice genes involved in defense responses against infection by the blast fungus magnaporthe grisea and fungal genes involved in growth within the host during a compatible interaction. a total of 511 clones was sequenced from a cdna library constructed from rice leaves (oryza sativa cv. nipponbare) infected with m. grisea strain 70-15 to generate 296 nonredundant ests. the sequences of 293 clones (57.3%) significantly matched national c ... | 2001 | 11763134 |