Publications
| Title | Abstract | Year Filter | PMID(sorted descending) Filter |
|---|
| purification of a membrane-bound udp-glucose:sterol [beta]-d-glucosyltransferase based on its solubility in diethyl ether. | membrane-bound udp-glucose:sterol [beta]-d-glucosyltransferase (udpg-sgtase) catalyzes the formation of steryl glucosides from udp-glucose and free sterols. this enzyme was purified from etiolated oat shoots (avena sativa l. cv alfred) in five steps. udpg-sgtase was solubilized from a microsomal fraction with the detergent n-octyl-[beta]-d-thioglucopyranoside and then extracted into diethyl ether. subsequent removal of the organic solvent, resolubilization with an aqueous buffer, and two column ... | 1994 | 12232266 |
| modulation of h+-atpase activity by fusicoccin in plasma membrane vesicles from oat (avena sativa l.) roots (a comparison of modulation by fusicoccin, trypsin, and lysophosphatidylcholine). | the fungal phytotoxin fusicoccin affects various transport processes in the plasma membrane of plant cells. the plasma membrane (pm) h+-atpase (ec 3.6.1.35) seems to be the primary target of fusicoccin action. the kinetics of the stimulation of the pm h+-atpase by fusicoccin was studied in pm vesicles isolated from oat (avena sativa cv adamo) roots by aqueous two-phase partitioning. considerable stimulation of activity was observed only when roots were treated with fusicoccin prior to the pm iso ... | 1994 | 12232167 |
| a contrast of the plasma membrane lipid composition of oat and rye leaves in relation to freezing tolerance. | the lipid composition of the plasma membrane isolated from leaves of spring oat (avena sativa l. cv ogle) was vastly different from that of winter rye (secale cereale l. cv puma). the plasma membrane of spring oat contained large proportions of phospholipids (28.8 mol% of the total lipids), cerebrosides (27.2 mol%), and acylated sterylglucosides (27.3 mol%) with lesser proportions of free sterols (8.4 mol%) and sterylglucosides (5.6 mol%). in contrast, the plasma membrane of winter rye contained ... | 1994 | 12232097 |
| a comparison of freezing injury in oat and rye: two cereals at the extremes of freezing tolerance. | a detailed analysis of cold acclimation of a winter rye (secale cereale l. cv puma), a winter oat (avena sativa l. cv kanota), and a spring oat cultivar (ogle) revealed that freezing injury of leaves of nonacclimated seedlings occurred at -2[deg]c in both the winter and spring cultivars of oat but did not occur in winter rye leaves until after freezing at -4[deg]c. the maximum freezing tolerance was attained in all cultivars after 4 weeks of cold acclimation, and the temperature at which 50% ele ... | 1994 | 12232096 |
| role of expansin in cell enlargement of oat coleoptiles (analysis of developmental gradients and photocontrol). | expansins are wall proteins that mediate a type of acid-induced extension in isolated plant cell walls (s. mcqueen-mason, d.m. durachko, d.j. cosgrove [1992] plant cell 4: 1425-1433). to assess the role of these proteins in the process of cell enlargement in living tissues, we compared the spatial and temporal growth patterns of oat (avena sativa l.) coleoptiles with four wall properties related to expansin action. these properties were (a) the ability of isolated walls and living segments to ex ... | 1993 | 12232025 |
| determination of auxin-dependent ph changes in coleoptile cell walls by a null-point method. | the present debate on the validity of the "acid-growth theory" of auxin (indole-3-acetic acid, iaa) action concentrates on the question of whether iaa-induced proton excretion into the cell wall is quantitatively sufficient to provide the shift in ph that is required to explain iaa-induced growth (see d.l. rayle, r.e. cleland [1992] plant physiol 99:1271-1274 for a recent apologetic review of the acid-growth theory). in the present paper a null-point method has been employed for determining the ... | 1993 | 12231942 |
| density gradient study of victorin-binding proteins in oat (avena sativa) cells. | victorin-binding proteins (vbps) in oat (avena sativa) cells were identified using native victorin and anti-victorin polyclonal antibodies. homogenates of oat tissues were fractionated in continuous or discontinuous sucrose density gradients or with an aqueous two-phase method, and covalent binding sites of victorin were detected by western blotting. in a 20 to 45% (w/w) sucrose continuous density gradient, the 100-kd vbp was located in fractions of 37 to 44% sucrose, with a peak at 39% sucrose. ... | 1993 | 12231915 |
| evidence for two indoleacetic acid-induced growth responses in the avena straight-growth indoleacetic acid assay. | floating avena sativa l. cv victory coleoptile segments were used to determine whether the straight-growth indoleacetic acid (iaa) assay can be reconciled with the avena curvature assay and the cholodny-went theory of photo- and gravitropism. measurements of segment length after 5 h yield sigmoid-shaped iaa dose-response curves with the growth rate leveling off at 1 [mu]m. however, measurements made at 24 h generate bell-shaped curves with maximal growth being induced by 10 [mu]m iaa. the differ ... | 1993 | 12231831 |
| two related biosynthetic pathways of mugineic acids in gramineous plants. | the biosynthesis of mugineic acids was studied by feeding 2h- or 13c-labeled compounds to water-cultured roots in several gramineous plants. the fate of labeled compounds was monitored by using 2h- and 13c-nuclear magnetic resonance. on investigating the proton changes during biosynthesis by feeding d,l-[3,3,4,4-d4]-methionine (98.6% 2h), 2h-labeled 2[prime]-deoxymugineic, mugineic, and 3-epihydroxymugineic acids were isolated from root washings of wheat (triticum aestivum l. cv minori), barley ... | 1993 | 12231828 |
| calcium antagonists inhibit sustained gibberellic acid-induced growth of avena (oat) stem segments. | the elongation response of avena sativa (oat) stem segments to gibberellic acid (ga3) is of large magnitude, with high hormonal sensitivity and specificity, but without cell division activity. this system is therefore an excellent model for mechanistic studies on higher plant cell elongation and the action of gibberellin. at millimolar concentrations, the calcium antagonists verapamil, d-600, nicardipine, diltiazem, bepridil, 8-(n,n,-diethylamino)-octyl-3,4,5-trimethoxybenzoate hcl, and lanthanu ... | 1993 | 12231695 |
| arginine decarboxylase is localized in chloroplasts. | plants, unlike animals, can use either ornithine decarboxylase or arginine decarboxylase (adc) to produce the polyamine precursor putrescine. lack of knowledge of the exact cellular and subcellular location of these enzymes has been one of the main obstacles to our understanding of the biological role of polyamines in plants. we have generated polyclonal antibodies to oat (avena sativa l.) adc to study the spatial distribution and subcellular localization of adc protein in different oat tissues. ... | 1995 | 12228631 |
| mgatp-dependent transport of phytochelatins across the tonoplast of oat roots. | in cd-exposed oat (avena sativa) roots cd was found to be associated primarily with the phytochelatin ([gamma]-glutamylcysteinyl)3-glutamic acid [([gamma]ec)3g], with a peptide to cd ratio of 1:3 (cysteine to cd ratio of 1:1), even though both ([gamma]ec)2g and ([gamma]ec)3g were present in the roots. phytochelatins are known to accumulate in the vacuoles of plant cells on exposure to cd, but the mechanism is not clear. here we present evidence for the transport of the phytochelatins ([gamma]ec) ... | 1995 | 12228436 |
| osmoregulation by oat coleoptile protoplasts (effect of auxin). | the effect of auxin on the physiology of protoplasts from growing oat (avena sativa l.) coleoptiles was investigated. protoplasts, isolated iso-osmotically from peeled oat coleoptile segments, were found to swell steadily over many hours. incubated in 1 mm cacl2, 10 mm kcl, 10 mm 2-(morpholino)ethanesulfonic acid/1,3-bis-[tris(hydroxymethyl)methylamino]propane, ph 6.5, and mannitol to 300 milliosmolal, protoplasts swelled 28.9% [plus or minus] 2.0 (standard error) after 6 h. addition of 10 [mu]m ... | 1996 | 12226237 |
| peroxygenase-catalyzed fatty acid epoxidation in cereal seeds (sequential oxidation of linoleic acid into 9(s),12(s),13(s)-trihydroxy-10(e)-octadecenoic acid). | peroxygenase-catalyzed epoxidation of oleic acid in preparations of cereal seeds was investigated. the 105,000g particle fraction of oat (avena sativa) seed homogenate showed high peroxygenase activity, i.e. 3034 [plus or minus] 288 and 2441 [plus or minus] 168 nmol (10 min)-1 mg-1 protein in two cultivars, whereas the corresponding fraction obtained from barley (hordeum vulgare and hordeum distichum), rye (secale cereale), and wheat (triticum aestivum) showed only weak activity, i.e. 13 to 138 ... | 1996 | 12226220 |
| phosphoryl group exchange between atp and adp catalyzed by h+-atpase from oat roots. | atp-adp exchange was estimated in the presence of plasma membrane h+-atpase of oat (avena sativa) roots partially purified with triton x-100 by measuring [14c]atp formation from [14c]adp. most studies were done at 0[deg]c. at ph 6.0 the exchange showed: (a) mg2+ requirement with a biphasic response giving maximal activity at 152 [mu]m and (b) insensitivity to ionic strength, [na+], and [k+]. atp and adp dependence were analyzed with a model in which nucleotide-enzyme interactions are at rapid-ra ... | 1997 | 12223778 |
| independent activation of cold acclimation by low temperature and short photoperiod in hybrid aspen. | temperate zone woody plants cold acclimate in response to both short daylength (sd) and low temperature (lt). we were able to show that these two environmental cues induce cold acclimation independently by comparing the wild type (wt) and the transgenic hybrid aspen (populus tremula x populus tremuloides michx.) line 22 overexpressing the oat (avena sativa) phytochrome a gene. line 22 was not able to detect the sd and, consequently, did not stop growing in sd conditions. this resulted in an impa ... | 2002 | 12177476 |
| toxicity of methyl tert-butyl ether to plants (avena sativa, zea mays, triticum aestivum, and lactuca sativa). | influence of methyl tert-butyl ether (mtbe) on the germination of seeds and growth of seedling plants were studied in laboratory experiments. test plants were wild oats (avena sativa), sweet corn (zea mays), wheat (triticum aestivum), and lettuce (lactuca sativa). seed germination, shoot growth, and root growth of plants exposed to different concentrations of mtbe in a moist soil were examined. seed germination and seedling growth in mtbe-contaminated soil were markedly reduced in all test plant ... | 2002 | 12152769 |
| the serine-rich n-terminal domain of oat phytochrome a helps regulate light responses and subnuclear localization of the photoreceptor. | phytochrome (phy) a mediates two distinct photobiological responses in plants: the very-low-fluence response (vlfr), which can be saturated by short pulses of very-low-fluence light, and the high-irradiance response (hir), which requires prolonged irradiation with higher fluences of far-red light (fr). to investigate whether the vlfr and hir involve different domains within the phya molecule, transgenic tobacco (nicotiana tabacum cv xanthi) and arabidopsis seedlings expressing full-length (fl) a ... | 2002 | 12114567 |
| repetition of the classical boysen-jensen and nielsen's experiment on phototropism of oat coleoptiles. | the classical experiment of phototropic response as reported by boysen-jensen and nielsen (1926), which supports the cholodny-went theory, was repeated in detail. in the original experiment, etiolated oat (avena sativa l. cv. victory) coleoptiles with mica inserted into their tip only showed a positive response when the mica was placed parallel toward the light source and not if it was inserted perpendicularly. on the contrary, we found a positive response irrespective of whether the mica was in ... | 2000 | 12090269 |
| ethanol sensitivity of rice and oat coleoptiles. | the ability to avoid the ethanol-induced injury was evaluated in rice (oryza sativa l.) and oat (avena sativa l.) coleoptiles. the growth of the rice and oat coleoptiles was inhibited by ethanol exogenously applied at concentrations greater than 200 and 30 mm, respectively. at 300 mm ethanol, oat coleoptiles were brown and flaccid but rice coleoptiles did not show any visible symptoms of toxicity. the acetaldehyde level in rice and oat coleoptiles was increased by exogenously applied ethanol and ... | 2002 | 12010475 |
| isolation of a/d and c genome specific dispersed and clustered repetitive dna sequences from avena sativa. | dna gel-blot and in situ hybridization with genome-specific repeated sequences have proven to be valuable tools in analyzing genome structure and relationships in species with complex allopolyploid genomes such as hexaploid oat (avena sativa l., 2n = 6x = 42; aaccdd genome). in this report, we describe a systematic approach for isolating genome-, chromosome-, and region-specific repeated and low-copy dna sequences from oat that can presumably be applied to any complex genome species. genome-spec ... | 2002 | 11962640 |
| chemistry and biology of phototropism-regulating substances in higher plants. | most people are familiar with the sight of a young seedling bending towards a window or the brightest source of light to which it is exposed. this directional growth response is known as phototropism, which is caused by a lateral growth-promoting auxin in the bending organ (cholodny-went theory, cited in high school textbook). recently, however, bruinsma et al., weiler et al., and hasegawa et al. independently found that the shaded half did not contain more auxin than the illuminated one. instea ... | 2001 | 11933243 |
| genetic and physical mapping of lrk10-like receptor kinase sequences in hexaploid oat (avena sativa l.). | oat receptor-like kinase gene sequences, homologous to the lrk10 gene from wheat (triticum aestivum l.), were mapped in oat (avena sativa l.). pcr primers designed from the wheat lrk10 were used to produce alrk10 from oat. two dna sequences, alrk1a1 and alrk4a5, were produced from primers designed from coding and noncoding regions of alrk10. their use as rflp probes indicated that the kinase genes mapped to four loci on different hexaploid oat 'kanota' x 'ogle' linkage groups (4_12, 5, 6, and 13 ... | 2002 | 11908651 |
| effects of commercial processing on levels of antioxidants in oats (avena sativa l.). | the effects of various commercial hydrothermal processes (steaming, autoclaving, and drum drying) on levels of selected oat antioxidants were investigated. steaming and flaking of dehulled oat groats resulted in moderate losses of tocotrienols, caffeic acid, and the avenanthramide bp (n-(4'-hydroxy)-(e)-cinnamoyl-5-hydroxy-anthranilic acid), while ferulic acid and vanillin increased. the tocopherols and the avenanthramides bc (n-(3',4'-dihydroxy-(e)-cinnamoyl-5-hydroxy-anthranilic acid) and bf ( ... | 2002 | 11902929 |
| modulating effects of oatmeal extracts in the sodium lauryl sulfate skin irritancy model. | the aim of the present study was to assess the anti-inflammatory activity of two topically applied oatmeal extracts, i.e. avena sativa and avena rhealba, using the sodium lauryl sulfate (sls) irritation model. at baseline, test areas on the volar surface of the upper arms of 12 healthy individuals were pretreated with the two extracts and their vehicle (petrolatum ointment) under occlusion for 2 h, and one site was left untreated. then a patch with a 1% sls solution was applied to the test sites ... | 2015 | 11867969 |
| [kinetics of mitotic rhythmic activity in oat (avena sativa) coleoptiles following irradiation]. | the analysis of different intensity (10-200 gy) irradiation influence on rhythmical processes in mitotic activity of oats coleoptiles was carries out. obtained results indicate that irradiation disorders phase and amplitude of the cell division rhythm in investigated material. this disturbance, as judged by doze dependence, is associated with unknown molecular structures. | 2015 | 11833332 |
| inhibition of gravitropism in oat coleoptiles by the calcium chelator, ethyleneglycol-bis-(beta-aminoethyl ether)-n,n'-tetraacetic acid. | a treatment period as brief as 8 h in 10(-3) m egta completely blocks gravitropism in 70-80% of the treated coleoptiles of oats (avena sativa l. cv. garry) without inhibiting growth. only about 10% of the plants perfused in water failed to exhibit gravitropism. subsequent perfusion of egta-treated plants with calcium completely restores gravitropism; post-perfusion with water does not. after perfusion in water for 10 h, gravistimulated oat coleoptile segments show the same asymmetry of 45ca dist ... | 1984 | 11829020 |
| amelioration of nickel phytotoxicity in muck and mineral soils. | in situ remediation (phytostabilization) is a cost-effective solution for restoring the productivity of metal-contaminated soils and protection of food chains. a pot experiment with wheat (triticum aestivum l.), oat (avena sativa l.), and redbeet (beta vulgaris l.) was conducted to test the ability of limestone and hydrous ferric oxide (hfo) to ameliorate ni phytotoxicity in two soils contaminated by particulate emissions from a nickel refinery. quarry muck (terric haplohemist; 72% organic matte ... | 2015 | 11790001 |
| a novel protein elicitor (panie) from pythium aphanidermatum induces multiple defense responses in carrot, arabidopsis, and tobacco. | a novel protein elicitor (panie(234)) from pythium aphanidermatum (edson) fitzp. was purified, microsequenced, and the corresponding cdna was cloned. the deduced amino acid sequence contains a putative eukaryotic secretion signal with a proteinase cleavage site. the heterologously expressed elicitor protein without the secretion signal of 21 amino acids (panie(213)) triggered programmed cell death and de novo formation of 4-hydroxybenzoic acid in cultured cells of carrot (daucus carota). program ... | 2001 | 11706166 |
| ruminal digestion by dairy cows grazing winter oats pasture supplemented with different levels and sources of protein. | six holstein cows fitted with ruminal cannulae were used in two simultaneous 3 x 3 latin squares to study the effects of protein supplements on ruminal fermentation and in situ crude protein degradability. cows rotationally grazed a winter oats (avena sativa l.) pasture and were supplemented with one of three concentrate supplements: 1) low protein sunflower meal (l-sm); 2) high protein sunflower meal (h-sm); or 3) high protein feather meal (h-fm). concentrates (6.5 kg/d) were offered in equal p ... | 2001 | 11699458 |
| molecular diversity and physical mapping of 5s rdna in wild and cultivated oat grasses (poaceae: aveneae). | 5s rdna repeats studied in five genera of aveneae have lengths between 285 and 329 bp (avena sativa, avena macrostachya, 26 species of helictotrichon, pseudarrhenatherum longifolium, lagurus ovatus, and trisetum spicatum). in only a single species (helictotrichon aetolicum) an additional repeat of 456 bp occurs infrequently. variation is largely due to insertions or deletions in the nontranscribed spacer as determined from sequences of 163 independent clones. the 5s gene of the aveneae studied i ... | 2001 | 11697916 |
| glycoside carbamates from benzoxazolin-2(3h)-one detoxification in extracts and exudates of corn roots. | zea mays was incubated with the natural phytotoxin benzoxazolin-2(3h)-one (boa) to investigate the detoxification process. a hitherto unknown detoxification product, 1-(2-hydroxyphenylamino)-1-deoxy-beta-gentiobioside 1,2-carbamate (3), was isolated and identified. a reinvestigation of known boa detoxification products by nmr methods led to the finding that the structure of benzoxazolin-2(3h)-one-n-beta-glucoside (1) first reported from avena sativa has to be revised. in fact, the correct struct ... | 2001 | 11672748 |
| an optomechanical transducer in the blue light receptor phototropin from avena sativa. | the phot1 (nph1) gene from avena sativa specifies the blue light receptor for phototropism, phototropin, which comprises two fmn-binding lov domains and a serine/threonine protein kinase domain. light exposure is conducive to autophosphorylation of the protein kinase domain. we have reconstituted a recombinant lov2 domain of a. sativa phototropin with various (13)c/(15)n-labeled isotopomers of the cofactor, fmn. the reconstituted protein samples were analyzed by nmr spectroscopy under dark and l ... | 2001 | 11606742 |
| intracellular localization of phytochrome in robinia pseudoacacia pulvini. | the intracellular localization of phytochrome in the pulvini of robinia pseudoacacia l. was analyzed by immunogold electron microscopy after red (r; 15 min) and far-red (fr; 5 min) irradiation 2 h after the beginning of the photoperiod. screening of the available antibodies by immunoblotting demonstrated that none of the oat (avena sativa l.) anti-phytochrome a (phy a) monoclonal antibodies) (mabs) detected robinia phytochrome. a putative robinia phy a was detected by immunoblotting using a mab ... | 2001 | 11556789 |
| genomic interspersions determine the size and complexity of transgene loci in transgenic plants produced by microprojectile bombardment. | the structure of transgene loci in six transgenic allohexaploid oat (avena sativa l.) lines produced using microprojectile bombardment was characterized using fluorescence in situ hybridization (fish) on extended dna fibers (fiber-fish). the transgene loci in five lines were composed of multiple copies of delivered dna interspersed with genomic dna fragments ranging in size from ca. 3 kb to at least several hundred kilobases, and in greater numbers than detected using southern blot analysis. alt ... | 2001 | 11550906 |
| gravitropism and phototropism of oat coleoptiles: post-tropic autostraightening and tissue shrinkage during tropism. | we measured changes in length on the two opposite sides of the red-light-grown oat (avena sativa l.) coleoptiles subjected to either gravitropic or phototropic stimulation and subsequently rotated on a horizontal clinostat. the length measurement was conducted using three 5 mm-long zones delimited by ink markers from the tip. curvature of each zone was analyzed from the length difference between the two sides. gravitropism was induced by displacing the seedling from the vertical by 30 degrees or ... | 1999 | 11542618 |
| coleoptiles are gravi-guiding systems vital for gravi-insensitive shoots of germinating grass seedlings. | surgical removal of the coleoptiles from germinating seedlings of secale cereale l., avena sativa l., and zea mays l. leads to a total loss of gravitropic response of the shoot without affecting growth. the principal function of coleoptiles is therefore to guide the gravi-insensitive shoot to the soil surface. | 1996 | 11541944 |
| changes in blue-light-dependent protein phosphorylation during the early development of etiolated oat seedlings. | blue light induced the phosphorylation of a 116-kda plasma-membrane-associated protein in dark-grown seedlings from avena sativa l. the response was restricted to the phototropically sensitive tissue of the coleoptile tip. surprisingly, this protein showed different properties in membrane preparations from plants that were grown for 3 d than in those from 5-d-old seedlings. in contrast to the younger coleoptiles, in 5-d-old seedlings phosphorylation of the 116-kda protein depended strictly on th ... | 1996 | 11541069 |
| phototropism involves a lateral gradient of growth inhibitors, not of auxin. a review. | during phototropic curvature, indolyl-3-acetic acid (iaa) remains evenly distributed in the hypocotyl of sunflower (helianthus annuus l.) and in the oat (avena sativa l.) coleoptile. at the irradiated side, growth inhibiting substances accumulate. in sunflower, basipetal movement of a growth factor is not involved, since the top of the seedling can be covered or removed without affecting the photo-tropic response; this response, moreover, is independent of the rate of elongation growth. the chem ... | 1989 | 11541033 |
| investigations into the possible regulation of negative gravitropic curvature in intact avena sativa plants and in isolated stem segments by ethylene and gibberellins. | using avena sativa l. cv. victory oat seedlings and excised p-1 stem segments (including the p-1 and p-2 internodes) the effect of exogenously supplied ethylene and the removal of ethylene on internodal extension and gravitropic bending was assessed. similarly, the ability of the excised system to respond to gravistimulation was assessed in the presence of inhibitors of ethylene action (agno3) and ethylene synthesis (3,5-diiodo-4-hydroxybenzoic acid and benzyl isothiocyanate; bitc). the producti ... | 1985 | 11540850 |
| 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 |
| calcium bridges are not load-bearing cell-wall bonds in avena coleoptiles. | i examined the ability of frozen-thawed avena sativa l. coleoptile sections under applied load to extend in response to the calcium chelators ethyleneglycol-bis-(beta-aminoethylether)-n,n,n',n'-tetraacetic acid (egta) and 2-[(2-bis-[carboxymethyl]amino-5-methylphenoxy)methyl]-6-methoxy-8-bis[carboxymethyl]aminoquinoline (quin ii). addition of 5 mm egta to weakly buffered (0.1 mm, ph 6.2) solutions of 2(n-morpholino) ethanesulfonic acid (mes) initiated rapid extension and wall acidification. when ... | 1989 | 11539809 |
| polyamine levels as related to growth, differentiation and senescence in protoplast-derived cultures of vigna aconitifolia and avena sativa. | we have previously reported that aseptically cultured mesophyll protoplasts of vigna divide rapidly and regenerate into complete plants, while mesophyll protoplasts of avena divide only sporadically and senesce rapidly after isolation. we measured polyamine titers in such cultures of vigna and avena, to study possible correlations between polyamines and cellular behavior. we also deliberately altered polyamine titer by the use of selective inhibitors of polyamine biosynthesis, noting the effects ... | 1985 | 11539806 |
| in vitro and in vivo protein phosphorylation in avena sativa l. coleoptiles: effects of ca2+, calmodulin antagonists, and auxin. | in vitro and in vivo protein phosphorylations in oat (avena sativa l.) coleoptile segments were analyzed by sodium dodecyl sulfate polyacrylamide gel electrophoresis and by two-dimensional gel electrophoresis. in vitro phosphorylation of several polypeptides was distinctly promoted at 1 to 15 micromolar free ca2+ concentrations. ca2(+)-stimulated phosphorylation was markedly reduced by trifluoperazine, chlorpromazine, and naphthalene sulfonamide (w7). two polypeptides were phosphorylated both un ... | 1986 | 11539102 |
| long-term acid-induced wall extension in an in-vitro system. | when frozen-thawed avena sativa l. coleoptile and cucumis sativa l. hypocotyl sections, under tension, are acid-treated, they undergo rapid elongation (acid-extension). the acid-extension response consists of two concurrent phases: a burst of extension which decays exponentially over 1-2 h (exe), and a constant rate of extension (ce) which can persist for at least 6h. the extension (delta l) is closely represented by the equation: delta l = a-a e(-kt) + c t where a is the total extension of the ... | 1987 | 11539098 |
| competency for graviresponse in the leaf-sheath pulvinus of avena sativa: onset to loss. | the development of the leaf-sheath pulvinus of oat (avena sativa l. cv. victory) was studied in terms of its competency to respond to gravistimulation. stages of onset of competency, maximum competency and loss of competency were identified, using the length of the supertending internode as a developmental marker. during the early phases in the onset of competency, the latency period between stimulus and graviresponse decreased and the steady state response rate increased significantly. when ful ... | 1988 | 11538847 |
| basis for changes in the auxin-sensitivity of avena sativa (oat) leaf-sheath pulvini during the gravitropic response. | during the gravitropic response, auxin-sensitivity of the lower flanks of leaf-sheath pulvini of avena sativa (oat) is at least 1000-fold higher than those of the upper flanks and non-gravistimulated pulvini. when the pulvini are treated with 1 mm ca2+, a 10-fold increase in auxin-sensitivity of the pulvini is observed. related to this difference in auxin-sensitivity, in vitro activation of the vanadate-sensitive h(-)-atpase by iaa was observed. results show that the activation of the h(+)-atpas ... | 1995 | 11538414 |
| elongation growth of the leaf sheath base of avena sativa seedlings: regulation by hormones and sucrose. | the leaf sheath base of the seedling of avena sativa was characterized for growth response to hormones and sucrose. six day old plants, raised under a 10:14 hr light:dark cycle, were excised at the coleoptilar node and 1 cm above the node for treatment. the growth of the leaf sheath base was promoted by gibberellic acid (ga3) and this response was dose dependent. the lag to response initiation was approximately 4 hr. growth with or without ga3 (10 micromoles) was transient, diminishing appreciab ... | 1991 | 11538405 |
| dynamics of auxin movement in the gravistimulated leaf-sheath pulvinus of oat (avena sativa). | the role of auxin redistribution in the graviresponse of the leaf-sheath pulvinus of oat (avena sativa l.) was assessed using 3h-indole-3-acetic acid (3h-iaa) preloaded into isolated pulvini. when pulvini were totally isolated from subtending nodal tissue as well as leaf-sheath and internode, gravistimulation failed to induce an asymmetric growth response. presence of either the nodal tissue or the internode/leaf-sheath tissue was sufficient to restore a normal graviresponse. gravistimulation of ... | 1991 | 11538277 |
| the outer epidermis of avena and maize coleoptiles is not a unique target for auxin in elongation growth. | a controversy exists as to whether or not the outer epidermis in coleoptiles is a unique target for auxin in elongation growth. the following evidence indicates that the outer epidermis is not the only auxin-responsive cell layer in either avena sativa l. or zea mays l. coleoptiles. coleoptile sections from which the epidermis has been removed by peeling elongate in response to auxin. the magnitude of the response is similar to that of intact sections provided the incubation solution contains bo ... | 1991 | 11538125 |
| the ph profile for acid-induced elongation of coleoptile and epicotyl sections is consistent with the acid-growth theory. | the acid-growth theory predicts that a solution with a ph identical to that of the apoplast of auxin-treated tissues (4.5.-5.0) should induce elongation at a rate comparable to that of auxin. different ph profiles for elongation have been obtained, however, depending on the type of pretreatment between harvest of the sections and the start of the ph-incubations. to determine the acid sensitivity under in vivo conditions, oat (avena sativa l.) coleoptile, maize (zea mays l.) coleoptile and pea (p ... | 1991 | 11538124 |
| auxin-induced growth of avena coleoptiles involves two mechanisms with different ph optima. | although rapid auxin-induced growth of coleoptile sections can persist for at least 18 hours, acid-induced growth lasts for a much shorter period of time. three theories have been proposed to explain this difference in persistence. to distinguish between these theories, the ph dependence for auxin-induced growth of oat (avena sativa l.) coleoptiles has been determined early and late in the elongation process. coleoptile sections from which the outer epidermis was removed to facilitate buffer ent ... | 1992 | 11537888 |
| altered growth response to exogenous auxin and gibberellic acid by gravistimulation in pulvini of avena sativa. | pulvini of excised segments from oats (avena sativa l. cv victory) were treated unilaterally with indoleacetic acid (iaa) or gibberellic acid (ga3) with or without gravistimulation to assess the effect of gravistimulation on hormone action. optimum pulvinus elongation growth (millimeters) and segment curvature (degrees) over 24 hours were produced by 100 micromolar iaa in vertical segments. the curvature response to iaa at levels greater than 100 micromolar, applied to the lower sides of gravist ... | 1988 | 11537872 |
| changes in the ultrastructure of cell walls, cellulose synthesis, and glucan synthase activity from gravistimulated pulvini of oat (avena sativa). | ultrastructural analyses of the cell walls from top and bottom halves of gravistimulated pulvini from oat leaves show a decrease in the density of material within the cell walls from the lower halves of pulvini after 24 h of gravistimulation. assays of cellulose synthesis with a 14c-sucrose pulse-chase experiment indicate no difference in the amount of new cellulose synthesized in top compared with bottom halves of gravistimulated pulvini. the highest rate of cellulose synthesis occurs with 12-2 ... | 1992 | 11537505 |
| cell wall and enzyme changes during the graviresponse of the leaf-sheath pulvinus of oat (avena sativa). | the graviresponse of the leaf-sheath pulvinus of oat (avena sativa) involves an asymmetric growth response accompanied by several asymmetric processes, including degradation of starch and cell wall synthesis. to understand further the cellular and biochemical events associated with the graviresponse, changes in cell walls and their constituents and the activities of related enzymes were investigated in excised pulvini. asymmetric increases in dry weight with relatively symmetric increases in wal ... | 1990 | 11537483 |
| polyamine binding to proteins in oat and petunia protoplasts. | previous work (a apelbaum et al. [1988] plant physiol 88: 996-998) has demonstrated binding of labeled spermidine (spd) to a developmentally regulated 18 kilodalton protein in tobacco tissue cultures derived from thin surface layer explants. to assess the general importance of such spd-protein complexes, we attempted bulk isolation from protoplasts of petunia and oat (avena sativa). in petunia, as in tobacco, fed radioactive spd is bound to protein, but in oat, spd is first converted to 1,3,-d ... | 1989 | 11537462 |
| comparison of the lipid composition of oat root and coleoptile plasma membranes: lack of short-term change in response to auxin. | the total lipid composition of plasma membranes (pm), isolated by the phase partitioning method from two different oat (avena sativa l.) tissues, the root and coleoptile, was compared. in general, the pm lipid composition was not conserved between these two organs of the oat seedling. oat roots contained 50 mole percent phospholipid, 25 mole percent glycolipid, and 25 mole percent free sterol, whereas comparable amounts in the coleoptile were 42, 39, and 19 mole percent, respectively. individual ... | 1989 | 11537452 |
| purification and identification of the fusicoccin binding protein from oat root plasma membrane. | fusicoccin (fc), a fungal phytotoxin, stimulates the h(+) -atpase located in the plasma membrane (pm) of higher plants. the first event in the reaction chain leading to enhanced h(+) -efflux seems to be the binding of fc to a fc-binding protein (fcbp) in the pm. we solubilized 90% of the fcbp from oat (avena sativa l. cv victory) root pm in an active form with 1% octyl-glucoside. the fcbp was stabilized by the presence of protease inhibitors. the fcbp was purified by affinity chromatography usin ... | 1989 | 11537448 |
| the role of calcium in growth induced by indole-3-acetic acid and gravity in the leaf-sheath pulvinus of oat (avena sativa). | leaf-sheath pulvini of excised segments from oat (avena sativa l.) were induced to grow by treatment with 10 micromoles indole-3-acetic acid (iaa), gravistimulation, or both, and the effects of calcium, egta, and calcium channel blockers on growth were evaluated. unilaterally applied calcium (10 mm cacl2) significantly inhibited iaa-induced growth in upright pulvini but had no effect on growth induced by either gravity or gravity plus iaa. calcium alone had no effect on upright pulvini. the calc ... | 1992 | 11536939 |
| gravitropism of oat and wheat coleoptiles: dependence on the stimulation angle and involvement of autotropic straightening. | gravitropism of oat (avena sativa l.) and wheat (triticum aestivum l.) coleoptiles was investigated in relation to the displacement angle or to the initially set stimulation angle (sa). we measured curvature rates at the early phase of curvature, before it was affected by the drop in sa resulting from the curvature response itself. the plot of the rates against the sines of initial sas revealed similar curves for oats and wheat, which approached saturation as the sine increased to unity. the two ... | 1997 | 11536867 |
| exposure of oat seedlings to blue light results in amplified phosphorylation of the putative photoreceptor for phototropism and in higher sensitivity of the plants to phototropic stimulation. | dark recovery of blue light-induced in vitro phosphorylation in oat (avena sativa l.) seedlings after in vivo preirradiation with blue light revealed different recovery kinetics for the coleoptile base and tip. although, in both cases, maximum in vitro phosphorylation was observed 90 min after in vivo blue light treatment, the phosphorylation levels for the entire base were about 3-fold higher than those found in nonpreirradiated plants. the tip response only slightly exceeded that of the dark c ... | 1997 | 11536818 |
| asymmetric, blue light-dependent phosphorylation of a 116-kilodalton plasma membrane protein can be correlated with the first- and second-positive phototropic curvature of oat coleoptiles. | the possible correlation between blue light-dependent phosphorylation of a 116-kd protein and phototropic responses of etiolated oat (avena sativa l.) seedlings was tested by a micromethod for protein phosphorylation. quantitation of the basipetal distribution of this protein showed that the in vitro 32p phosphorylation values declined exponentially from tip to node, with more than 50% of the total label being found in the uppermost 5 mm. nonsaturating preirradiation of the coleoptiles in vivo r ... | 1997 | 11536817 |
| infrared light-emitting diode radiation causes gravitropic and morphological effects in dark-grown oat seedlings. | oat (avena sativa cv seger) seedlings were irradiated with ir light-emitting diode (led) radiation passed through a visible-light-blocking filter. infrared led irradiated seedlings exhibited differences in growth and gravitropic response when compared to seedlings grown in darkness at the same temperature. thus, the oat seedlings in this study were able to detect ir led radiation. these findings call into question the use of ir led as a safe-light for some photosensitive plant response experimen ... | 1996 | 11536734 |
| hormonal and gravitropic specificity in the regulation of growth and cell wall synthesis in pulvini and internodes from shoots of avena sativa l. (oat). | segments can be cut from the peduncular-1 internode of oat (avena sativa l.) shoots so as to contain the graviresponsive leaf-sheath pulvinus and gibberellin-sensitive internodal tissue. incorporation of [14c]glucose was used to monitor cell wall synthesis in these two tissues as affected by gravistimulus, indoleacetic acid (iaa), gibberellic acid (ga3), and fusicoccin (fc). pulvinar cell wall synthesis was promoted by iaa and fc (both within about 1 h), as well as by gravistimulus (starting bet ... | 1995 | 11536686 |
| cloning and characterisation of chlorophyll synthase from avena sativa. | the chlorophyll synthase gene from oat (avena sativa) was cloned and expressed in escherichia coli. the deduced amino acid sequence consists of 378 amino acids including a presequence of 46 amino acids. deletion mutants show that a core protein comprising amino acid residues 88 to 377 is enzymatically active. the sequence of the mature protein shows 85% identity with the chlorophyll synthase of arabidopsis thaliana and 62% identity with the chlorophyll synthase of synechocystis pcc 6803. the gen ... | 2001 | 11501754 |
| purification and biochemical properties of phytochromobilin synthase from etiolated oat seedlings. | plant phytochromes are dependent on the covalent attachment of the linear tetrapyrrole chromophore phytochromobilin (p phi b) for photoactivity. in planta, biliverdin ix alpha (bv) is reduced by the plastid-localized, ferredoxin (fd)-dependent enzyme p phi b synthase to yield 3z-p phi b. here, we describe the >50,000-fold purification of p phi b synthase from etioplasts from dark-grown oat (avena sativa l. cv garry) seedlings using traditional column chromatography and preparative electrophoresi ... | 2001 | 11500553 |
| evaluation and refinement of a continuous seed germination and early seedling growth test for the use in the ecotoxicological assessment of soils. | four higher plant species (avena sativa l., oat; lepidium sativum l., cress; brassica rapa metzg., turnip; and phaseolus vulgaris l., bush bean) and 15 soils including five mineral oil-contaminated soils were tested to assess a soil-based continuous seed germination and early seedling growth bioassay. seed germination was recorded and the shoot biomass of 14-day seedlings measured. an automatic self-watering system was compared with the daily hand watering. results obtained from this study show ... | 2001 | 11459155 |
| high frequency of cytogenetic aberration in transgenic oat (avena sativa l.) plants. | cytological abnormalities were observed in transgenic oat (avena sativa l. cv. gaf/park-1) produced by microprojectile bombardment of mature seed-derived highly regenerative tissues. of the plants from 48 independent transgenic lines examined, plants from only 20 lines (42%) were karyotypically normal (2n=6x=42) without detectable chromosomal aberrations; plants from 28 lines (58%) had chromosomal variation, i.e. aneuploids and structural changes. no significant difference in cytological aberrat ... | 2001 | 11448750 |
| tween-20 activates and solubilizes the mitochondrial membrane-bound, calmodulin dependent nad+ finase of avena sativa l. | among different treatments assayed, a mix of a nonionic detergent (5% tween-20) with 0.5 m nacl was found to solubilize a large part of the calmodulin-dependent nad+ kinase bound to the inner mitochondrial membrane. it also stimulated its activity by increasing 7 times the maximal velocity. activity stimulation was also observed with phosphatidylcholine, phosphatidylethanolamine and with reductants (hso3 and dtt). this solubilized nad+ kinase and the calmodulin-dependent cytosoluble isoform disp ... | 2001 | 11447505 |
| changes in starch content in oat (avena sativa) shoot pulvini during the gravitropic response. | in order to determine if components of the signal transduction pathway are involved in starch metabolism during the gravitropic response, the effects of inhibitors of phosphoprotein phosphatases and protein kinases (oa), and calcium channel blockers (lacl3), on gravitropic bending and starch levels in gravisensitive node/pulvini of oat shoots were examined. among the compounds tested, okadaic acid (oa) and lanthanum chloride (lacl3) showed the strongest inhibitory effects on the negative gravitr ... | 2001 | 11432919 |
| oxidative responses of resistant and susceptible cereal leaves to symptomatic and nonsymptomatic cereal aphid (hemiptera: aphididae) feeding. | the impact of the leaf-chlorosis-eliciting russian wheat aphid, diuraphis noxia (mordvilko), and the nonchlorosis-eliciting bird cherry-oat aphid, rhopalosiphum padi (l.), feeding on d. noxia-susceptible and -resistant cereals was examined during the period (i.e., 3, 6, and 9 d after aphid infestation) that leaf chlorosis developed. after aphid number, leaf rolling and chlorosis ratings, and fresh leaf weight were recorded on each sampling date, total protein content, peroxidase, catalase, and p ... | 2001 | 11425032 |
| bonding of hydroxycinnamic acids to lignin: ferulic and p-coumaric acids are predominantly linked at the benzyl position of lignin, not the beta-position, in grass cell walls. | a suspension in dichloromethane-water (18:1, v/v) of various fractions containing hydroxycinnamic acid ester-ether bridges between lignin and polysaccharides prepared from cell walls of matured oat (avena sativa l.) intemodes, and a solution of their acetates in the same solvent, were treated with 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (ddq). this reagent selectively cleaves benzyl ether and ester linkages of negatively charged aromatic nuclei. the sample treated with ddq was directly hydroly ... | 2001 | 11423145 |
| supplemental dietary protein for grazing dairy cows: reproduction, condition loss, plasma metabolites, and insulin. | an experiment was conducted over a 2-yr period to investigate the influence of grain crude protein (cp) and rumen undegradable protein (rup) concentration on reproduction and energy status of dairy cows grazing annual ryegrass (lolium multiflorum) and oats (avena sativa). holstein cows (n = 122) were blocked by calving group [partum (0 d postpartum) vs. postpartum (41 +/- 19 d postpartum at study initiation)] and assigned to grain supplements containing high cp [22.8% of dry matter (dm)], modera ... | 2001 | 11352167 |
| a linkage map of hexaploid oat based on grass anchor dna clones and its relationship to other oat maps. | a cultivated oat linkage map was developed using a recombinant inbred population of 136 f6:7 lines from the cross 'ogle' x 'tam o-301'. a total of 441 marker loci, including 355 restriction fragment length polymorphism (rflp) markers, 40 amplified fragment length polymorphisms (aflps), 22 random amplified polymorphic dnas (rapds), 7 sequence-tagged sites (stss), 1 simple sequence repeat (ssr), 12 isozyme loci, and 4 discrete morphological traits, was mapped. fifteen loci remained unlinked, and 4 ... | 2001 | 11341736 |
| identification of a sucrose diester of a substituted beta-truxinic acid in oats. | a novel compound, 4,4'-dihydroxy-3,3'-dimethoxy-beta-truxinic acid esterified to sucrose through the fructosyl 3-and 6-carbons (1), was isolated from oat grains (avena sativa l.). its structure was determined by a combination of mass spectrometry and 1-d and 2-d nmr. the amounts of 1 in groats of six different oat cultivars ranged from 101 to 150 microg g(-1) (dry wt). none was detected in the hulls. the free diacid, 4,4'-dihydroxy-3,3'-dimethoxy-beta-truxinic acid (2), could not be detected in ... | 2001 | 11324915 |
| synthesis, absolute configuration and biological activity of both enantiomers of 2-(5,6-dichloro-3-indolyl)propionic acid: new dichloroindole auxins. | racemic 2-(5,6-dichloro-3-indolyl)propionic acid (5,6-cl2-2-ipa) was synthesized from 5,6-dichloroindole-3-acetic acid (5,6-cl2-iaa) by successive esterification, methoxycarbonylation, methylation, and double hydrolysis. the racemate was converted to the diastereomeric esters of (s)-(-)-1-phenylethyl alcohol. these were separated by hplc into two optically active diastereomers and then hydrolyzed with p-tsoh to the optically active enantiomers of 5,6-cl2-2-ipa. the absolute configurations of bot ... | 2001 | 11302158 |
| 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 |
| impact of elevated ozone on chlorophyll a fluorescence in field-grown oat (avena sativa). | oat (avena sativa) plants were grown in the field near the urban area of valencia, eastern spain. the data on air quality showed that ozone was the main phytotoxic pollutant present in ambient air reaching a 7-h mean of 46 nl l(-1) and a maximum hourly peak of 322 nl l(-1). the effect of ambient ozone on psii activity was examined by measurements of chlorophyll (chl) a fluorescence. in leaves with visible symptoms, the function of psii was changed at high actinic irradiances. nonphotochemical qu ... | 2001 | 11275221 |
| a role for inositol 1,4,5-trisphosphate in gravitropic signaling and the retention of cold-perceived gravistimulation of oat shoot pulvini. | plants sense positional changes relative to the gravity vector. to date, the signaling processes by which the perception of a gravistimulus is linked to the initiation of differential growth are poorly defined. we have investigated the role of inositol 1,4,5-trisphosphate (insp(3)) in the gravitropic response of oat (avena sativa) shoot pulvini. within 15 s of gravistimulation, insp(3) levels increased 3-fold over vertical controls in upper and lower pulvinus halves and fluctuated in both pulvin ... | 2001 | 11244128 |
| 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 |
| mapping maize sequences to chromosomes using oat-maize chromosome addition materials. | oat- (avena sativa) maize (zea mays) chromosome additions are produced by crossing maize and oat. during early embryo development maize chromosomes are preferentially eliminated, and oat plants are often recovered that retain a single maize chromosome. each of the 10 maize chromosomes recently has been isolated as a separate oat-maize addition. we describe here the mapping of 400 maize sequences to chromosomes using polymerase chain reaction and dna from the oat-maize addition material. fifty of ... | 2001 | 11244104 |
| a complete set of maize individual chromosome additions to the oat genome. | all 10 chromosomes of maize (zea mays, 2n = 2x = 20) were recovered as single additions to the haploid complement of oat (avena sativa, 2n = 6x = 42) among f(1) plants generated from crosses involving three different lines of maize to eight different lines of oat. in vitro rescue culture of more than 4,300 immature f(1) embryos resulted in a germination frequency of 11% with recovery of 379 f(1) plantlets (8.7%) of moderately vigorous growth. some f(1) plants were sectored with distinct chromoso ... | 2001 | 11244103 |
| identification and characterization of a heat-induced isoform of aldolase in oat chloroplast. | an analysis of protein synthesis at elevated temperatures in oat (avena sativa) leaves revealed a heat-induced 44 kda polypeptide. a cdna library of heat-treated leaves was constructed and screened with specific antibodies raised against this 44 kda polypeptide. a clone encoding the 44 kda protein was identified as a form of the chloroplast-localized fructose-bisphosphate aldolase (ec 4.1.2.13). northern and western blot analyses indicated heat-induced accumulation of the chloroplast aldolase is ... | 2000 | 11197324 |
| isolation, purification, and characterization of glutathione s-transferase from oat (avena sativa) seedlings. | glutathione s-transferase (gst) from oat seedlings was purified by ammonium sulfate precipitation and glutathione (gsh) affinity chromatography. sodium dodecyl sulfate-polyacrylamide gel electrophoresis revealed the presence of two major protein subunits with molecular masses of 29 and 31 kda, respectively. isoelectric focusing revealed a major band with pi of 3.43 and a minor band with pi of 7.42. kinetic analysis with respect to 1-chloro-2,4-dinitrobenzene (cdnb) as substrate revealed a km of ... | 2000 | 11195966 |
| feasibility of using lignin isolated from forages by solubilization in acetyl bromide as a standard for lignin analyses. | lignin concentration can be measured in plants by the acetyl bromide-soluble lignin spectrophotometric method; however, as with any spectrophotometric method, a reliable standard is needed. in the present experiments, lignin was extracted from each of the forages under study with the acetyl bromide reagent. the lignin isolated with acetyl bromide (liab) was then used as the reference standard in the acetyl bromide-soluble lignin (absl) analysis, which was compared with the acid detergent lignin ... | 2000 | 11132828 |
| aux/iaa proteins are phosphorylated by phytochrome in vitro. | auxin/indole-3-acetic acid (aux/iaa) genes encode short-lived transcription factors that are induced as a primary response to the plant growth hormone iaa or auxin. gain-of-function mutations in arabidopsis genes, shy2/iaa3, axr3/iaa17, and axr2/iaa7 cause pleiotropic phenotypes consistent with enhanced auxin responses, possibly by increasing aux/iaa protein stability. semidominant mutations shy2-1d, shy2-2, axr3-1, and axr2-1 induce ectopic light responses in dark-grown seedlings. because genet ... | 2000 | 11115889 |
| effect of maturity on degradation kinetics of sod-seeded cereal grain forage grown in northern arkansas. | wheat (triticum aestivum l.), oat (avena sativa l.), and rye (secale cereale l.) were overseeded into a dormant bermudagrass (cynodon dactylon (l.) pers.) sod and harvested at 3-wk intervals throughout march, april, may, and early june. plant growth stage was documented for each forage on each harvest date, and harvested forages were evaluated for forage quality characteristics. degradation kinetics of dm and ndf for these forages were evaluated by the in situ method. fractional degradation rate ... | 2000 | 11104269 |
| classical and biochemical endpoints in the evaluation of phytotoxic effects caused by the herbicide trichloroacetate. | three terrestrial plant species, oat (avena sativa ), chinese cabbage (brassica campestris cv. chinensis) and lettuce (lactuca sativa), were exposed to different concentrations of herbicide tca (sodium trichloroacetate) in a growth test according to guideline oecd # 208. classical (i.e. germination and biomass) and biochemical (i.e., antioxydant enzyme activities) endpoints were investigated. germination rate decreased significantly at 3.9 mg tca kg dry soil(-1) (for oat and lettuce) and 62.5 mg ... | 2000 | 11064042 |
| the influence of glycerol and chloroplast lipids on the spectral shifts of pigments associated with nadph: protochlorophyllide oxidoreductase from avena sativa l. | dark-grown angiosperm seedlings lack chlorophylls, but accumulate protochlorophyllide a complexed with the light-dependent enzyme nadph:protochlorophyllide oxidoreductase. previous investigators correlated spectral heterogeneity of in vivo protochlorophyllide forms and a shift of chlorophyllide forms from 680 to 672 nm (shibata shift) occurring after irradiation, with intact membrane structures which are destroyed by solubilization. we demonstrate here that the various protochlorophyllide forms ... | 2000 | 11034350 |
| characterization of protein and transcript levels of the chaperonin containing tailless complex protein-1 and tubulin during light-regulated growth of oat seedlings. | in grass seedlings the network of cortical microtubules is reorganized during light-dependent growth of coleoptiles and mesocotyls. we investigated the effects of light-dependent growth on the relative steady-state levels of the mrnas and protein levels of alpha-tubulin and the epsilon-subunit of the chaperonin containing tailless complex protein-1 in oat (avena sativa) coleoptiles, which were grown in different light conditions to establish different growth responses. the soluble pools of the e ... | 2000 | 10982445 |
| production and characterization of maize chromosome 9 radiation hybrids derived from an oat-maize addition line. | in maize (zea mays l., 2n = 2x = 20), map-based cloning and genome organization studies are often complicated because of the complexity of the genome. maize chromosome addition lines of hexaploid cultivated oat (avena sativa l., 2n = 6x = 42), where maize chromosomes can be individually manipulated, represent unique materials for maize genome analysis. maize chromosome addition lines are particularly suitable for the dissection of a single maize chromosome using radiation because cultivated oat ... | 2000 | 10978296 |
| evidence of active nadp(+) phosphatase in dormant seeds of avena sativa l. | freshly-harvested seeds of avena sativa l. do not germinate when imbibed at temperatures higher than 25 degrees c. this high temperature dormancy is due to the seed coats, and to the low activities of glycolysis and the oxidative pentose phosphate pathway (opp) in the embryo. the analysis by exclusion chromatography of soluble nadp(+) phosphatase activities of embryos revealed two isoforms: a 37 kda isoform present in both dormant and after-ripened caryopses, and a second isoform, with an appare ... | 2000 | 10944152 |
| photochemical and mutational analysis of the fmn-binding domains of the plant blue light receptor, phototropin. | the plant photoreceptor phototropin is an autophosphorylating serine-threonine protein kinase activated by uv-a/blue light. two domains, lov1 and lov2, members of the pas domain superfamily, mediate light sensing by phototropin. heterologous expression studies have shown that both domains function as fmn-binding sites. although three plant blue light photoreceptors, cry1, cry2, and phototropin, have been identified to date, the photochemical reactions underlying photoactivation of these light se ... | 2000 | 10924135 |
| high frequency of cytogenetic aberration in transgenic oat (avena sativa l.) plants. | cytological abnormalities were observed in transgenic oat (avena sativa l. cv. gaf/park-1) produced by microprojectile bombardment of mature seed-derived highly regenerative tissues. of the plants from 48 independent transgenic lines examined, plants from only 20 lines (42%) were karyotypically normal (2n=6x=42) without detectable chromosomal aberrations; plants from 28 lines (58%) had chromosomal variation, i.e. aneuploids and structural changes. no significant difference in cytological aberrat ... | 2000 | 10908808 |
| antioxidant activity and total phenolics in selected cereal grains and their different morphological fractions. | the purpose of this study was to examine the antioxidant properties of water and 80% methanolic extracts of cereal grains and their different morphological fractions. wheat (triticum aestivum l.) cv. almari and cv. henika, barley (hordeum vulgare l.) cv. gregor and cv. mobek, rye (secale cereale l.) cv. dańkowskie zlote, oat (avena sativa l.) cv. slawko and buckwheat (fagopyrum esculentum moench) cv. kora were used. pc (l-alpha-phosphatidylcholine) liposome system and spectrophotometric assay of ... | 2000 | 10888490 |
| biosynthesis of avenacins and phytosterols in roots of avena sativa cv. image. | in keeping with the proposal that avenacin biosynthesis is restricted to the tips of primary roots of oat seedlings, the incorporation of radioactivity from r-[2-(14)c]mevalonic acid (mva) into avenacins and beta-amyrin by serial sections of primary roots was found to be more-or-less restricted to root tip sections. squalene synthase (sqs) (ec 2.5.1.21) and 2,3-oxidosqualene:beta-amyrin cyclase (os beta ac) (ec 5.4.99) were also most active in these sections. the incorporation of radiolabel from ... | 2000 | 10872206 |
| complex structure of knobs and centromeric regions in maize chromosomes. | the recovery of maize (zea mays l.) chromosome addition lines of oat (avena sativa l.) from oat x maize crosses enables us to analyze the structure and composition of individual maize chromosomes via the isolation and characterization of chromosome-specific cosmid clones. restriction fragment fingerprinting, sequencing, and in situ hybridization were applied to discover a new family of knob associated tandem repeats, the tr1, which are capable of forming fold-back dna segments, as well as a new ... | 2015 | 10857197 |
| thermal effect of co(2) on apoplastic ice in rye and oat during freezing. | meristematic tissues from rye (secale cereale) and oat (avena sativa) were studied in an isothermal calorimeter at -3 degrees c. when the frozen tissue was placed in the calorimeter, the pressure increased within 4 d to 25 and 9 kpa above ambient pressure in the sample vessels containing crowns of rye and oat, respectively. concurrently, the thermal output went down to -194 microw in rye over the 4-d period; this negative thermal activity could be accounted for by ice melting in the plants. when ... | 2000 | 10712550 |
| chromosomal localization of cotransformed transgenes in the hexaploid cultivated oat avena sativa l. using fluorescence in situ hybridization. | fluorescence in situ hybridization (fish) was used to localize two transgenes (gus and bar), carried on plasmids pact-1f and puba, respectively, on mitotic metaphase squashes of t1 plants of the cultivated hexaploid oat avena sativa l. cotransformed by microprojectile bombardment of embryogenic callus. among the eight progeny analysed by fish in each of two lines, we detected plants null, hetero- and homozygous for the two genes in one line, and plants null and heterozygous for the two genes in ... | 2000 | 10692010 |
| antioxidant capacity of oat (avena sativa l.) extracts. 2. in vitro antioxidant activity and contents of phenolic and tocol antioxidants. | oat milling fractions were examined for concentrations of total phenolics, tocols, and phenolic acids and in vitro antioxidant activity to determine their potential as dietary antioxidants. methanolic extracts of pearling fractions, flour and aspirations from flaking, and trichomes had high, intermediate, and low antioxidant activities, respectively, evaluated by the beta-carotene bleaching method. pearling fractions were also highest in total phenolics and tocols. p-hydroxybenzoic acid, vanilli ... | 1999 | 10606549 |