Publications
| Title | Abstract | Year(sorted ascending) Filter | PMID Filter |
|---|
| 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 |
| glycolytic activity in embryos of pisum sativum and of non-dormant or dormant seeds of avena sativa l. expressed through activities of pfk and ppi-pfk. | a quantitative cytochemical assay for ppi-pfk activity in the presence of fru-2,6-p2 is described along with its application to determine levels of activity in embryos of pisum sativum and avena sativa. the activity of atp-pfk has also been studied in parallel as have pfk activities during the switch from dormant to non-dormant embryos in avena sativa. ppi-pfk activity has been demonstrated in all tissues of pisum sativum embryos and of avena sativa embryos including the scutellum and the aleuro ... | 1989 | 2541117 |
| phytochrome structure: peptide fragments from the amino-terminal domain involved in protein-chromophore interactions. | we have undertaken a study of the structure of the amino-terminal domain of the phytochrome polypeptide purified from avena sativa l. amino-acid sequencing was used to indentify arginine 52 as the precise location of a conformation-specific cleavage of phytochrome by subtilisin. the location of the epitopes for a class of monoclonal antibodies designated type 2 has been shown to be located between approx. 10 and 20 kilodaltons (kda) from the amino terminus. these two new spatial markers, in addi ... | 1989 | 24212743 |
| gas exchange of ears of cereals in response to carbon dioxide and light : i. relative contributions of parts of the ears of wheat, oat, and barley to the gas exchange of the whole organ. | one cultivar each of spring wheat (triticum aestivum l. cv. arkas), oat (avena sativa l. cv. lorenz), and barley (hordeum vulgare l. cv. aramir) was chosen in order to study the relative contributions of individual bracts to the gas exchange of whole ears. the distribution and frequency of the stomata on the bracts were examined. gas exchange was measured at normal atmospheric co2 (330 μbar) and at high co2 (2000 μbar) on intact ears and on ears from which glumes or lemmas and pleae (wheat and o ... | 1989 | 24212553 |
| ph-dependence of extension growth in avena coleoptiles and its implications for the mechanism of auxin action. | the ph-dependence of acid-induced growth in excised segments of avena sativa coleoptiles has been reinvestigated in the ph range 3 to 7. in contrast to previous reports (e.g. dl rayle [1973] planta 114: 63-73), only acidic buffers with a ph below 5.0 induce an extension response. a ph of 3.5 to 4.0 is required to mimic auxin-mediated growth. very similar ph-response curves are obtained with both intact (abraded) and peeled coleoptiles. these results agree with the recent finding of a similarly l ... | 1989 | 16666736 |
| domain structure of phytochrome from avena sativa visualized by electron microscopy. | highly purified phytochrome from avena sativa was visualized by electron microscopy after negative staining with uranyl acetate and after rotary shadowing with platinum. the particle shape was variable in both types of specimens, but tripartite structures resembling a 'y' were consistently observed. the tripartite substructure is composed of three globular domains each having a diameter of 7 to 8 nm and equally spaced in an equilateral triangle. the dimensions of the tripartite particle measured ... | 1989 | 2727087 |
| 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 |
| 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 |
| phytochrome - all regions marked by a set of monoclonal antibodies reflect conformational changes. | monoclonal antibodies to defined locations on six regions of the phytochrome molecule (from avena sativa l. or zea mays l.) were each found to have a different affinity toward the farred-absorbing form of phytochrome (pfr) and the red-absorbing form (pr). the differences were small, but were consistently shown by antibodies which bind to the vicinity of the aminoterminus, the carboxylterminus and to sequences in between. it seems that the conformational differences between pr and pfr extend over ... | 1989 | 24212493 |
| regulation of transplasmalemma electron transport in oat mesophyll cells by sphingoid bases and blue light. | long-chain sphingoid bases inhibit transplasmalemma electron transport in certain animal cells in part by inhibiting protein phosphorylation. as a first step in determining whether similar regulatory processes exist for cell surface redox activity in plants, peeled leaf segments of avena sativa l. cv garry were exposed to sphingoid bases and other long chain lipids. sphingoid bases which are the most active inhibitors of protein kinase c in animal cells inhibit transplasmalemma electron transpor ... | 1989 | 16666708 |
| revision of the theory of phototropism in plants: a new interpretation of a classical experiment. | went's classical experiment on the diffusion of auxin activity from unilaterally illuminated oat coleoptile tips (went 1928), was repeated as precisely as possible. in agreement with went's data with theavena curvature assay, the agar blocks from the illuminated side of oat (avena sativa l. cv. victory) coleoptile tips had, on an average, 38% of the auxin activity of those from the shaded side. however, determination of the absolute amounts of indole-3-acetic acid (iaa) in the agar blocks, using ... | 1989 | 24213051 |
| characterization of a polyphosphoinositide phospholipase c from the plasma membrane of avena sativa. | a phosphoinositide-specific phospholipase c activity was identified in oat root (avena sativa, cv victory) plasma membranes purified by separation in an aqueous two-phase polymer system. the enzyme is highly active toward inositol phospholipids but only minimally active toward phosphatidylethanolamine and phosphatidylcholine. activity approaches maximal levels at 200 micromolar phosphatidylinositol 4-phosphate (pip) and is highly dependent on calcium; it is inhibited by 1 millimolar egta and is ... | 1989 | 16667176 |
| diclofop-methyl increases the proton permeability of isolated oat-root tonoplast. | diclofop-methyl (methyl ester of 2-[4-(2',4'-dichlorophenoxy)phenoxy]propionate; 100 micromolar) and diclofop (100 micromolar) inhibited both atp- and ppi-dependent formation of h(+) gradients by tonoplast vesicles isolated from oat (avena sativa l., cv dal) roots. diclofop-methyl (1 micromolar) significantly reduced the steady-state h(+) gradient generated in the presence of atp. the ester (diclofop-methyl) was more inhibitory than the free acid (diclofop) at ph 7.4, but this relative activity ... | 1989 | 16667096 |
| analysis of avenin proteins and the expression of their mrnas in developing oat seeds. | we have isolated and characterized cdna clones encoding avenins, the prolamine storage proteins of oat seeds. sequence analysis shows that avenins are a related group of polypeptides and that their mrnas differ from each other by point mutations and small insertions and deletions. avenin proteins have structural homology to the alpha/beta-gliadins and gamma-gliadins of wheat, the b-hordeins of barley, and the gamma-secalins of rye. hybridization analysis of dna from various diploid, tetraploid, ... | 1989 | 2535531 |
| biosynthesis of the tonoplast h-atpase from oats. | to determine whether the tonoplast-type h(+)-atpase was differentially synthesized in various parts of the oat seedling, sections of 4-day-old oat (avena sativa l. var lang) seedlings were labeled in vivo with [(35)s]methionine and atpase subunits were precipitated with polyclonal antisera. atpase subunits were detected in all portions of the seedling with the exception of the seed. lesser amounts of the 60 and 72 kilodalton polypeptides of the atpase were found in apical regions (0-5 millimeter ... | 1989 | 16666699 |
| a wheat alpha-amy2 promoter is regulated by gibberellin in transformed oat aleurone protoplasts. | gibberellin (ga(3))-responsive aleurone protoplasts isolated from avena sativa have been successfully used as a transient expression system to analyse promoter fusions between the wheat alpha-amylase gene alpha-amy2/54 and the reporter gene gus. following peg-mediated uptake of plasmid dna, transient expression directed by the alpha-amy2/54 promoter was found to be regulated in the same way as the endogenous oat alpha-amylase genes. expression was thus dependent on the inclusion of ga(3) in the ... | 1989 | 16453890 |
| immunolocalization of avenin and globulin storage proteins in developing endosperm of avena sativa l. | the seed storage proteins of oats (avena sativa l.) are synthesized and assembled into vacuolar protein bodies in developing endosperm tissue. we used double-label immunolocalization to study the distribution of these proteins within protein bodies of the starchy endosperm. when sections of developing oat endosperm sampled 8 d after anthesis were stained with uranyl acetate and lead citrate, the vacuolar protein bodies consisted of light-staining regions which were usually surrounded by a darker ... | 1989 | 24212898 |
| 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 |
| suitability of small grains as hosts of meloidogyne species. | seven cultivars of wheat, five of oat, one of rye, and four of barley were tested as hosts for meloidogyne incognita, m. javanica, or m. arenaria under greenhouse conditions where soil temperature ranged from 21 to 34 c. reproduction rates of all nematode species were high on all cultivars, except m. javanica and m. arenaria on 'brooks' and 'florida 501' oat. meloidogyne incognita and m. javanica produced more eggs on roots of 'rutgers' tomato than on cultivars of wheat, oat, rye, or barley. | 1989 | 19287666 |
| unusual hepatic parenchymal crystalloid material and biliary microliths in goats. | investigation into an outbreak of suspected photosensitivity in boer goats grazing green oats (avena sativa) led to the finding of microscopical parenchymal crystaloid material and biliary microliths in the livers of 3 ewes that were killed for necropsy. neither tribulus terrestris nor panicum spp. occurred on the farm. further investigation resulted in the isolation, from leaf spots on the oat leaves, of the fungus drechslera campanulata, cultures of which have been shown to be highly toxic to ... | 1989 | 2634769 |
| 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 |
| cloning and sequencing of protochlorophyllide reductase. | putative protochlorophyllide reductase cdna clones (252 and 113) were isolated from an etiolated-oat (avena sativa) cdna library. these were used to indirectly characterize a further clone, p127, isolated from a lambda-phage gt11 cdna library. the latter (1.15 kb in length) was sequenced, and the derived amino acid sequence was shown to be remarkably similar to that derived from chemical analysis of a cnbr-cleavage fragment of the purified reductase, p127 codes for more than 95% of the reductase ... | 1990 | 1689568 |
| reproduction of pratylenchus penetrans on potato and crops grown in rotation with potato. | the relative suitability of potato and crops frequently grown in rotation with potato as hosts for pratylenchus penetrans was evaluated. suitability of rye, wheat, corn, oat, sorgho-sudangrass, and potato were compared in pot studies based on ratios of final population : initial population density and densities of nematodes in roots at harvest. population densities increased more on potato, oat, and corn than on rye, wheat, and sorgho-sudangrass. there were no differences among the four rye cult ... | 1990 | 19287696 |
| antigenic relationships between petunia peroxidase a and specific peroxidase isoenzymes in other solanaceae. | a highly specific rabbit antiserum raised against peroxidase (prxa) from petunia (petunia hybrida) was used to investigate the antigenic relatedness of peroxidases in the solanaceae. after sds-page of crude leaf extracts from a large number of species of this family, immunoblotting revealed that cross-reacting protein bands were present in all species tested. in order to determine whether these protein bands represent peroxidases, the peroxidase isoenzymes in thorn apple (datura stramonium l.), ... | 1990 | 24220819 |
| evolutionary and tissue-specific control of expression of multiple acyl-carrier protein isoforms in plants and bacteria. | we have examined the occurrence of multiple acyl-carrier protein (acp), isoforms in evolutionarily diverse species of higher and lower plants. isoforms were resolved by native polyacrylamide gel electrophoresis (page), and were detected by western blotting or fluorography of [(3)h]-palmitate-labelled acps. multiple isoforms of acp were found in leaf tissue of the monocotyledons avena sativa and hordeum vulgare and dicotyledons arabidopsis thaliana, cuphea wrightii, and brassica napus. lower vasc ... | 1990 | 24202013 |
| an h-atpase assay: proton pumping and atpase activity determined simultaneously in the same sample. | a continuous spectrophotometric assay of h(+)-atpase activity was developed by combining two well-known methods for measuring proton pumping and atpase activity. proton uptake into plasma membrane vesicles from avena sativa l. (cv rhiannon) was monitored as the absorbance decrease at 495 nm of the deltaph probe acridine orange. simultaneously, atpase activity was measured by following the absorbance decrease at 340 nanometers by coupling atp hydrolysis enzymatically to the oxidation of nadh. thi ... | 1990 | 16667867 |
| immunocytolocalization of plasma membrane h-atpase. | the localization of plasma membrane h(+)-atpase has been studied at the optical microscope level utilizing frozen and paraffin sections of avena sativa and pisum sativum, specific anti-atpase polyclonal antibody, and second antibody coupled to alkaline phosphatase. in leaves and stems the atpase is concentrated at the phloem, supporting the notion that it generates the driving force for phloem loading. in roots the atpase is concentrated at both the periphery (rootcap and epidermis) and at the c ... | 1990 | 16667670 |
| pectin esterification is spatially regulated both within cell walls and between developing tissues of root apices. | monoclonal antibodies recognizing un-esterified (jim5) and methyl-esterified (jim7) epitopes of pectin have been used to locate these epitopes by indirect immunofluorescence and immunogold electron microscopy in the root apex of carrot (daucus carota l.). both antibodies labelled the walls of cells in all tissues of the developing root apex. immunogold labelling observed at the level of the electron microscope indicated differential location of the pectin epitopes within the cell walls. the un-e ... | 1990 | 24196931 |
| photoregulation of beta-tubulin mrna abundance in etiolated oat and barley seedlings. | the effect of light on the abundance of beta-tubulin mrna was measured in etiolated avena sativa l. and hordeum vulgare l. seedlings. slot blot analysis employing an oat beta-tubulin cdna clone was used to measure beta-tubulin mrna levels. white light induced a 45% decrease in oat beta-tubulin mrna abundance by 2 hours after transfer. a saturating red light pulse induced 40 and 55% decreases in beta-tubulin mrna levels in oats and barley, respectively. recovery of beta-tubulin mrna levels was ob ... | 1990 | 16667578 |
| senescence and stomatal aperture as affected by antibiotics in darkness and light. | in leaves of barley (hordeum vulgare), as previously found with oats (avena sativa), a group of six antibiotics that interfere in different ways with the sequence dna --> mrna --> protein all delay senescence in the dark, acting to conserve chlorophyll (chl) and protein and also to open the stomata. among the active compounds is chloramphenicol, which had previously been reported to act only on procaryotes. it is now shown that all these compounds with senescence-delaying action in darkness have ... | 1990 | 16667337 |
| intracellular localisation of phytochrome in oat coleoptiles by electron microscopy : dependence on light pretreatments and the amount of the active, far-red-absorbing form. | the intracellular localisation of phytochrome in oat (avena sativa l. cv. garry oat) coleoptiles was analysed by electron microscopy. serial ultrathin sections of resin-embedded material were indirectly immunolabeled with polyclonal antibodies against phytochrome together with a gold-coupled second antibody. the limits of detectability of sequestered areas of phytochrome (saps) were analysed as a function of light pretreatments and amounts of the far-red absorbing form of phytochrome (pfr) estab ... | 1990 | 24202016 |
| solubilization and reconstitution of the oat root vacuolar h/ca exchanger. | calcium is sequestered into vacuoles of oat (avena sativa l.) root cells via a h(+)/ca(2+) antiporter, and vesicles derived from the vacuolar membrane (tonoplast) catalyze an uptake of calcium which is dependent on protons (ph gradient [deltaph] dependent). the first step toward purification and identification of the h(+)/ca(2+) antiporter is to solubilize and reconstitute the transport activity in liposomes. the vacuolar h(+)/ca(2+) antiporter was solubilized with octylglucoside in the presence ... | 1990 | 16667279 |
| genomic sequence of a 12s seed storage protein gene from oat (avena sativa l. cv. 'solidor'). | 1990 | 2326176 | |
| free amino acid composition of leaf exudates and phloem sap : a comparative study in oats and barley. | comparisons were made between the free amino acid composition in leaf exudates and that in pure phloem sap, using twin samples taken from a single leaf of two oat (avena sativa l.) and three barley (hordeum vulgare l.) varieties. leaf exudate was collected in a 5 mm edta-solution (ph 7.0) from cut leaf blades and phloem sap was obtained through excised aphid (rhopalosiphum padi l.) stylets. fluorescent derivatives of amino acids were obtained using 9-fluorenylmethyl chloroformate and were separa ... | 1990 | 16667250 |
| 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 |
| [comparison of presence of ascorbic acid and the appearance of ascorbate peroxidase activity in embryos of avena sativa l]. | avena sativa l. grains are devoid of ascorbic acid (aa) and of oxidative enzymes (aa oxidase and aa peroxidase), while both reducing enzymes (afr reductase and dha reductase) are present. aa biosynthesis in the embryos starts after 12-14 hours of germination and at the same time aa peroxidase activity is detectable. during the following 14 hours the aa peroxidase activity rises up to 28 nmoles/aa oxidated/min/mg/prot. incubation of avena embryos with gl (the last precursor of aa according to the ... | 1990 | 2390226 |
| oat mesophyll protoplasts: their response to various feeder cultures. | oat (avena sativa l.) mesophyll protoplasts were recently demonstrated to be capable of dedifferentiation, repeated divisions, and colony formation. since the development of oat mesophyll protoplasts is decisively influenced by the nature of the used feeder culture (species, variety and concentration), we conducted a systematic study of this parameter. generally, graminaceous feeders promoted protoplast proliferation, while dicot species repressed protoplast divisions. the beneficial effect of t ... | 1990 | 24232678 |
| fructan precipitation from a water/ethanol extract of oats and barley. | fructan was precipitated from a water and ethanol extract of oat (avena sativa l.) and barley (hordeum vulgare l.). the degree of polymerization and response on a differential refractometer, based on peak area and height, was compared to fructan collected from a lead-based hplc column and to commercially available inulin. statistically significant differences are discussed. | 1990 | 16667347 |
| aluminum ions induce oat protoplasts to produce an extracellular (1-->3)beta-d-glucan. | aluminum chloride induced mesophyll protoplasts of oat (avena sativa) to produce an extracellular polysaccharide (eps). eps induced by alcl(3) appeared identical to that produced in response to the phytotoxin victorin (jd walton, ed earle [1985] planta 165: 407-415). al ions at 1 millimolar were toxic to protoplasts, but maximum eps production occurred at a sublethal concentration of 200 micromolar, assayed at ph 6.0. as measured by incorporation of [(14)c]glucose, alcl(3) stimulated eps product ... | 1990 | 16667679 |
| intracellular protein phosphorylation in oat (avena sativa l.) protoplasts by phytochrome action: involvement of protein kinase c. | phosphorylations of two proteins (27 kda, 32 kda) in oat cells were dependent on phytochrome action. to determine which kinase system(s) for the phosphorylation of these two proteins are controlled by the phytochrome, involvement of the ca2+/dg dependent protein kinase (protein kinase c) was first investigated. when a protein kinase c inhibitor (1-(5-isoquinoline sulfonyl)-2-methylpiperazine:h-7) or the inositol phospholipid metabolic blocker li+ was added into the cell suspension, respectively, ... | 1990 | 2163631 |
| co-ordination of chromophore-apoprotein synthesis in the developing leaf of avena sativa l. | 1990 | 2373249 | |
| functional xylem anatomy in root-shoot junctions of six cereal species. | in cereals, the formation of safety zones in the root-shoot junction could protect the vessels of roots from embolism originating in the shoot. the root-shoot junction was examined both anatomically, with a light microscope, and experimentally, using a pressurized-air method, in the base of seminal and adventitious roots of maize (zea mays l. cv. seneca 60-ii), a corngrass mutation of maize (cg mutant), sorghum (sorghum bicolor l. cv. ho-pak), winter oats (avena sativa l. cv. ogle), spring wheat ... | 1991 | 24193938 |
| avena sativa l. contains three phytochromes, only one of which is abundant in etiolated tissue. | phytochrome from leaves of light-grown oat (avena sativa l. cv. garry) plants is characterized with newly generated monoclonal antibodies (mabs) directed to it. the results indicate that there are at least two phytochromes in green oat leaves, each of which differs from the phytochrome that is most abundant in etiolated oat tissue. when analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (sds-page) with reference to 124-kilodalton (kda) phytochrome from etiolated oats, the two ... | 1991 | 24193935 |
| large-scale partial purification of phytochrome from green leaves of avena sativa l. | phytochrome from 10 or 11-d-old oat (avena sativa l. cv. garry) leaves, which were harvested just prior to sunset from plants grown in a greenhouse in the absence of supplemental illumination, was purified an estimated 250-fold by sequential poly(ethylenimine) and ammonium-sulfate fractionations, followed by linear-gradient hydroxyapatite chromatography. compared to earlier protocols, the one presented here is substantially more rapid, provides improved yield and purity, can be used with larger ... | 1991 | 24193933 |
| effects of diclofop and diclofop-methyl on membrane potentials in roots of intact oat, maize, and pea seedlings. | growth and electrophysiological studies in roots of intact diclofop-methyl susceptible and resistant seedlings were conducted to test the hypothesis that the herbicide acts primarily as a proton ionophore. the ester formulation of diclofop, at 0.2 micromolar, completely inhibited root growth in herbicide-susceptible oat (avena sativa l.) after a 96 hour treatment, but induced only a delayed transient depolarization of the membrane potential in oat root cortical cells. root growth in susceptible ... | 1991 | 16668091 |
| electrical membrane properties of leaves, roots, and single root cap cells of susceptible avena sativa: effect of victorin c. | the effect of the purified host-selective toxin victorin c, a cyclized penta peptide, was compared to that of cccp and vanadate on membrane functions of susceptible leaves, roots, and single root cap cells of avena sativa with conventional electrophysiology. the plasmalemma depolarized irreversibly by about 80 millivolts and to below the diffusion potential within 1 hour. concentrations as low as 12.5 picomolar were effective in the susceptible but not the resistant cultivar. electrical membrane ... | 1991 | 16668038 |
| diurnal periodicity of chalcone-synthase activity during the development of oat primary leaves. | chalcone-synthase (chs) activity was followed during the development of primary leaves of oat (avena sativa l.) seedlings grown under different illumination conditions. continuous darkness and continuous light resulted in similar time courses of enzyme activity. the maximum of chs activity in etiolated leaves was delayed by 1 d and reached about half the level of that of light-grown leaves. in seedlings grown under defined light-dark cycles a diurnal rhythm of chs activity and its protein level ... | 1991 | 24193751 |
| prediction of f3 row performance from f2 individual plant data in oats. | parameters estimated from a gardner-eberhart analysis of the f2 generation of a six-parent diallel in oats (avena sativa l.) were used to compare methods for predicting the performance of f3 row plots. the prediction methods were: (1) individual f2 plant performance (f2i), (2) parent average plus f2 plot deviations (pf2), (3) parent average plus weighted f2 plot deviations (pf2p), (4) best linear unbiased prediction (blup) of parent average plus f2 plot deviations (bpf2), and (5) blup plus weigh ... | 1991 | 24221162 |
| 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 |
| characterization of acyllipid: sterol glucoside acyltransferase from oat (avena sativa l.) seedlings. | membranous fractions from leaves of oat seedlings readily convert cholesterol beta-d-glucoside into its 6'-o-acyl derivative using endogenous acyllipids as acyl sources. experiments with delipidated enzyme preparations showed that among acyllipids present in oat leaves digalactosyldiacylglycerols are evidently the best acyl donors in this reaction. beside of sterol glucosides, the enzyme can acylate beta-d-glucosides of several other steroids, although at very different rates. | 1991 | 1796705 |
| lipids of plasma membranes prepared from oat root cells : effects of induced water-deficit tolerance. | plasma membranes were isolated from oat (avena sativa) roots by the phase-partitioning method. the membranes were exposed to repeated periods of moderate water-deficit stress, and a water-deficit tolerance was induced (acclimated plants). the plasma membranes of the controls (nonacclimated plants) were characterized by a high phospholipid content, 79% of total lipids, cerebrosides (9%) containing hydroxy fatty acids (>90% 24:1-oh) and free sterols, acylated sterylglucosides, sterylglucosides, an ... | 1991 | 16668310 |
| 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 auxintreated 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 (pis ... | 1991 | 24186576 |
| expression of ap 3, 4 and 5 isophytochromes in etiolated oat seedlings (avena sativa l.). | type 1 phytochrome from etiolated oat seedlings was digested with v-8 protease. microsequencing of a 13 kda fragment yielded a sequence of 31 amino acids. the fragment starting with the alanine residue at position 427 of the entire phytochrome amino acid sequence revealed a heterogeneity (threonine, alanine and asparagine) at position 10. this demonstrates that the phytochrome type a genes ap3, 4 and 5 are expressed as proteins. | 1991 | 1881964 |
| some properties of the h-atpase activity present in root plasmalemma of avena sativa l. two different enzymes or one enzyme with two atp sites? | the effects of mg2+, k+ and atp on a h-atpase activity from a native plasmalemma fraction of oat roots were explored at 20 degrees c and ph 6.5. in the presence of 3 mm atp and no k+, h-atpase activity vs. [mg2+] approached a monotonic activation but it became biphasic, with a decline above 3 mm mg2+, in the presence of 20 mm k+. mg2+ inhibition occurred also in k-free solutions when [atp] was lowered to 0.05 mm. also, an apparent monotonic h-atpase activation by [k+] at 3.0 mm atp was transform ... | 1991 | 1827349 |
| 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 | 24186577 |
| western blot analysis of cereal grain prolamins using an antibody to carboxyl-linked indoleacetic acid. | a monoclonal antibody raised against carboxyl-linked iaa was used in western blot analysis of storage proteins from kernels of avena sativa, pennisetum americanum, sorghum bicolor, and zea mays. iaa or an iaa-like molecule is associated with the ethanolsoluble protein fraction of the seed. western blotting of commercial zein, the major storage protein of maize, along with physicochemical evidence reported by leverone et al. ([1991] plant physiol, 96: 1070-1075) indicated that iaa is linked with ... | 1991 | 16668300 |
| conjugation of ubiquitin to proteins from green plant tissues. | conjugation of the polypeptide ubiquitin to endogenous proteins was studied in oat (avena sativa l.) plants, and particularly in green tissues. conjugating activity in leaf extracts was different from that in root extracts, and in both was less than in etiolated tissue. the conjugates were identified by sodium dodecyl sulfate polyacrylamide gel electrophoresis (sds-page), and their formation was both time- and atp-dependent and had a ph optimum of about 8.2. the assay had a high affinity for atp ... | 1991 | 16668183 |
| photoresponses of transgenic tobacco plants expressing an oat phytochrome gene. | the physiological responses of transgenic tobacco (nicotiana tabacum l.) plants that express high levels of an introduced oat (avena sativa l.) phytochrome (phya) gene to various light treatments are compared with those of wild-type (wt) plants. seeds, etiolated seedlings, and light-grown plants from a homozygous transgenic tobacco line (9a4) constructed by keller et al. (embo j, 8, 1005-1012, 1989) were treated with red (r), far-red (fr), or white light (wl) with or without supplemental fr ligh ... | 1991 | 24186338 |
| callus formation and plant regeneration from somatic embryos of oat (avena sativa l.). | globular-stage somatic embryos were isolated by vortexing friable, embryogenic callus of oat (avena sativa l.) followed by fractionation based on size. somatic embryos were most frequently found in the 300-380 μm size fraction. friable, embryogenic callus was reinitiated from 55% of isolated somatic embryos. fertile plants were regenerated from 22% of isolated somatic embryos. reinitiation of callus from somatic embryos and growth of friable, embryogenic callus was inhibited by the selective age ... | 1991 | 24221588 |
| patch clamping protoplasts from vascular plants : method for the quick isolation of protoplasts having a high success rate of gigaseal formation. | a method is described for the isolation of protoplasts (pisum sativum, phaseolus vulgaris, avena sativa, arabidopsis thaliana) in preparation for ion flux studies using patch clamp electrophysiology. protoplasts that have been exposed to hydrolytic, cell wall degrading, enzymes for as little as 5 minutes form gigaseals (seal resistance higher than 10 giga ohm) with the patch pipette with success rates greater than 40%. sealing of these protoplasts is fast, averaging less than 2 minutes. this met ... | 1991 | 16668586 |
| abscisic acid and ethylene increase in heterodera avenae-infected tolerant or intolerant oat cultivars. | the relationship between root stunting caused by the cereal cyst nematode and levels of two root growth inhibiting hormones, abscisic acid and ethylene, was investigated in aseptically cultured root segments and in intact roots of two oat cultivars differing in tolerance to the nematode. cultured root segments of oat cultivars new zealand cape (tolerant) and sual (intolerant) were inoculated with sterilized heterodera avenae second-stage juveniles. suppressed growth of root axes and emerged late ... | 1991 | 19283149 |
| monoclonal antibodies directed to phytochrome from green leaves of avena sativa l. cross-react weakly or not at all with the phytochrome that is most abundant in etiolated shoots of the same species. | seven monoclonal antibodies (mabs) have been prepared to phytochrome from green oat (avena sativa l. cv. garry) leaves. one of these mabs (go-1) cross-reacts with apoprotein of the phytochrome that is most abundant in etiolated oat shoots as assessed by immunoblot assay of fusion proteins expressed in escherichia coli. the epitope for this mab is located between amino acids 618 and 686 in the primary sequence of type 3 phytochrome (hershey et al. 1985, nucleic acids res. 13, 8543-8559), which is ... | 1991 | 24193934 |
| molecular cloning and sequencing of cdnas encoding the proteolipid subunit of the vacuolar h(+)-atpase from a higher plant. | to understand the molecular structure of the vacuolar h(+)-translocating atpase from plants, cdnas encoding the n,n'-dicyclohexylcarbodiimide-binding 16-kda proteolipid from oat (avena sativa l. var. lang) have been obtained. a synthetic oligonucleotide corresponding to a region of the bovine proteolipid cdna (mandel, m., moriyama, y., hulmes, j.d., pan, y.-c.e., nelson, h., and nelson, n. (1988) proc. natl. acad. sci. u.s.a. 85, 5521-5524) was used to screen an oat cdna library constructed in l ... | 1991 | 1831453 |
| heterologous encapsidation in mixed infections among four isolates of barley yellow dwarf virus. | we used immunohybridization and elisa to investigate heterologous encapsidation (transcapsidation and phenotypic mixing) between paired isolates of barley yellow dwarf virus (bydv) in doubly infected oat plants, avena sativa l. cv. clintland 64. virons in samples extracted from plants doubly infected with two viruses were trapped with an antibody specific to one virus, and the nucleic acids of the trapped virions were identified with a cdna probe specific to the other. heterologous encapsidation ... | 1991 | 1895059 |
| evaluation of methods for sampling, recovery, and enumeration of bacteria applied to the phylloplane. | determining the fate and survival of genetically engineered microorganisms released into the environment requires the development and application of accurate and practical methods of detection and enumeration. several experiments were performed to examine quantitative recovery methods that are commonly used or that have potential applications. in these experiments, erwinia herbicola and enterobacter cloacae were applied in greenhouses to blue lake bush beans (phaseolus vulgaris) and cayuse oats ... | 1991 | 16348404 |
| xyloglucan antibodies inhibit auxin-induced elongation and cell wall loosening of azuki bean epicotyls but not of oat coleoptiles. | polyclonal antibodies were raised in rabbits against isoprimeverose (xyl(1)glc(1)), xyloglucan heptasaccharides (xyl(3)glc(4)), and octasaccharides (gal(1)xyl(3)glc(4)). antibodies specific for hepta- and octasaccharides suppressed auxin-induced elongation of epicotyl segments of azuki bean (vigna angularis ohwi and ohashi cv takara). these antibodies also inhibited auxin-induced cell wall loosening (decrease in the minimum stress-relaxation time and the relaxation rate of the cell walls) of azu ... | 1991 | 16668221 |
| covalent binding sites of victorin in oat leaf tissues detected by anti-victorin polyclonal antibodies. | polyclonal antibodies against victorin, the host-specific toxin produced by cochliobolus victoriae, were raised in rabbits immunized with a victorin-bovine serum albumin conjugate. the antibodies were purified from serum by protein a column chromatography and characterized by indirect and direct enzymelinked immunosorbent assays (elisa). the concentration of victorin that inhibited anti-victorin antibody binding by 50% was 10 nanograms per milliliter in an indirect elisa. the lowest concentratio ... | 1992 | 16668602 |
| proton transport activity of the purified vacuolar h-atpase from oats : direct stimulation by cl. | to determine whether the detergent-solubilized and purified vacuolar h(+)-atpase from plants was active in h(+) transport, we reconstituted the purified vacuolar atpase from oat roots (avena sativa var lang). triton-solubilized atpase activity was purified by gel filtration and ion exchange chromatography. incorporation of the vacuolar atpase into liposomes formed from escherichia coli phospholipids was accomplished by removing triton x-100 with sm-2 bio-beads. atp hydrolysis activity of the rec ... | 1992 | 16669020 |
| arginine decarboxylase of oats is clipped from a precursor into two polypeptides found in the soluble enzyme. | we have examined soluble oat (avena sativa) arginine decarboxylase by probing its structure with polyclonal antibodies that separately recognize amino-terminal and carboxyl-terminal antigens and with a monoclonal antibody that immunoprecipitates enzyme activity. these experiments indicated that oat arginine decarboxylase is clipped from a 66,000-d precursor polypeptide into 42,000- and 24,000-d produce polypeptides. both of these are found in the enzyme and may be held together by disulfide bond ... | 1992 | 16652937 |
| regulation of tabtoxin production by the lema gene in pseudomonas syringae. | pseudomonas syringae pv. coronafaciens, a pathogen of oats, was mutagenized with tn5 to generate mutants defective in tabtoxin production. from a screen of 3,400 kanamycin-resistant transconjugants, seven independent mutants that do not produce tabtoxin (tox-) were isolated. although the tn5 insertions within these seven mutants were linked, they were not located in the previously described tabtoxin biosynthetic region of p. syringae. instead, all of the insertions were within the p. syringae pv ... | 1992 | 1314808 |
| identification of the three major coeliac immunoreactive proteins and one alpha-amylase inhibitor from oat endosperm. | six chloroform/methanol-soluble proteins from oat endosperm (avena sativa) have been isolated and characterized by a purification procedure based on extraction with volatile solvents, followed by reversed-phase high performance liquid chromatography. three of these proteins, with an assessed molecular weight of 25,000, 27,000 and 32,000 da, respectively, have been identified by immunoblotting using coeliac sera, as the major coeliac serum iga-binding components of oat endosperm. the n-terminal a ... | 1992 | 1526282 |
| blue light activates a specific protein kinase in higher plants. | blue light mediates the phosphorylation of a membrane protein in seedlings from several plant species. when crude microsomal membrane proteins from dark-grown pea (pisum sativum l.), sunflower (helianthus annuus l.), zucchini (cucurbita pepo l.), arabidopsis (arabidopsis thaliana l.), or tomato (lycopersicon esculentum l.) stem segments, or from maize (zea mays l.), barley (hordeum vulgare l.), oat (avena sativa l.), wheat (triticum aestivum l.), or sorghum (sorghum bicolor l.) coleoptiles are i ... | 1992 | 16653043 |
| immunochemical analysis of the temporal and tissue-specific expression of an avena sativa plasma membrane determinant. | an immunoglobulin mk monoclonal (f8ive9) antibody raised against oat (avena sativa cv garry) root homogenate has been produced and characterized. the predominant target bound by this antibody is a 62-kilodalton protein (p62) that is expressed in both oat root and oat shoot cells. treatment of the oat antigen with periodate, or with recombinant n-glycanase, affects the f8ive9 binding to the antigen, suggesting that the specific epitope for this monoclonal antibody involves a carbohydrate determin ... | 1992 | 16668621 |
| 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 |
| kinetics of the vacuolar h-pyrophosphatase : the roles of magnesium, pyrophosphate, and their complexes as substrates, activators, and inhibitors. | the responses of the vacuolar membrane (tonoplast) proton-pumping inorganic pyrophosphatase (h(+)-ppase) from oat (avena sativa l.) roots to changes in mg(2+) and pyrophosphate (ppi) concentrations have been characterized. the kinetics were complex, and reaction kinetic models were used to determine which of the various ppi complexes were responsible for the observed responses. the results indicate that the substrate for the oat root vacuolar h(+)-ppase is mg(2)ppi and that this complex is also ... | 1992 | 16653186 |
| induction of udp-glucose:salicylic acid glucosyltransferase in oat roots. | a udp-glucose:salicylic acid 3-o-glucosyltransferase (ec 2.4.1.35) (gtase) from oat (avena sativa l. cv dal) root extracts was assayed in vitro using [(14)c]salicylic acid (sa) and an ion exchange column to separate sa from beta-glucosylsalicylic acid. the gtase, present at a very low constitutive level, was inducible to 23 times the constitutive level. when excised roots were exposed to sa at ph 6.5, the specific activity of the enzyme increased within 1.5 h, peaked after 8 to 10 h, and then de ... | 1992 | 16653092 |
| partial purification and properties of an inducible uridine 5'-diphosphate-glucose-salicylic acid glucosyltransferase from oat roots. | a salicylic acid (sa)-inducible uridine 5'-diphosphate (udp)-glucose:sa 3-o-glucosyltransferase was extracted from oat (avena sativa l. cv dal) roots. reverse phase high-performance liquid chromatography or anion exchange chromatography was used to separate sa from the product, beta-o-d-glucosylsalicylic acid. the soluble enzyme was purified 176-fold with 5% recovery using a combination of ph fractionation, anion exchange, gel filtration, and chromatofocusing chromatography. the partially purifi ... | 1992 | 16652983 |
| short-term effects of rhizosphere microorganisms on fe uptake from microbial siderophores by maize and oat. | effects of rhizosphere microorganisms on fe uptake by oat (avena sativa) and maize (zea mays) were studied in short-term (10 h) nutrient solution experiments. fe was supplied either as microbial siderophores (pseudobactin [psb] or ferrioxamine b [fob]) or as phytosiderophores obtained as root exudates from barley (epi-3-hydroxy-mugineic acid [hma]) under varied population densities of rhizosphere microorganisms (axenic, uninoculated, or inoculated with different microorganism cultures). when mai ... | 1992 | 16652982 |
| intracellular redistribution of phytochrome in etiolated soybean (glycine max l.) seedlings. | the intracellular distribution of phytochrome in hypocotyl hooks of etiolated soybean (glycine max l.) has been examined by immunofluorescence using a newly produced monoclonal antibody (soy-1) directed to phytochrome purified from etiolated soybean shoots. cortical cells in the hook region exhibit the strongest phytochrome-associated fluorescence, which is diffusely distributed throughout the cytosol in unirradiated, etiolated seedlings. a redistribution of immunocytochemically detectable hytoc ... | 1992 | 24178207 |
| phytochrome levels in light-grown avena change in response to end-of-day irradiations. | the effect of 15-minute end-of-day irradiations on photoreversible phytochrome levels in light-grown oat (avena sativa l., cv garry) seedlings was investigated. oat seedlings were grown in a cycle of 8 hours of natural daylight and 16 hours of complete darkness, from sowing until harvest at day 10. the level of extractable, photoreversible phytochrome per unit fresh weight was 60% higher after end-of-day far-red irradiation than after either end-of-day red irradiation or end-of-day far-red follo ... | 1992 | 16669098 |
| 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 |
| distribution of phytochrome and chlorophyll-a/b-binding-protein mrnas in etiolated avena seedlings. | in 4-d-old dark-grown oat (avena sativa l.) seedlings, the majority of the type-i-phytochrome (phya) mrna was found within 10 mm of the tip of the coleoptile sheath and in the mesocotyl node; almost none was detected in the enclosed primary leaf. in contrast, chlorophyll-a/b-binding-protein (cab) mrnas were found almost exclusively in the enclosed primary leaf and were barely detectable in total-rna samples from the coleoptile sheath or mesocotyl node of red-light-treated etiolated seedlings. se ... | 1992 | 24178148 |
| subunit composition and organization of the vacuolar h-atpase from oat roots. | the vacuolar h(+)-translocating atpase (h(+)-atpase), originally reported to consist of three major subunits, has been further purified from oat roots (avena sativa var lang) to determine the complete subunit composition. triton-solubilized atpase activity was purified by gel filtration on sephacryl s400 and ion-exchange chromatography (q-sepharose). atp hydrolysis activity of purified preparations was inhibited by 100 nanomolar bafilomycin a(1), a specific vacuolar-type atpase inhibitor. the pu ... | 1992 | 16668846 |
| dissociation and reassembly of the vacuolar h-atpase complex from oat roots. | conditions for the dissociation and reassembly of the multi-subunit vacuolar proton-translocating atpase (h(+)-atpase) from oat roots (avena sativa var lang) were investigated. the peripheral sector of the vacuolar h(+)-atpase is dissociated from the membrane integral sector by chaotropic anions. membranes treated with 0.5 molar ki lost 90% of membrane-bound atp hydrolytic activity; however, in the presence of mg(2+) and atp, only 0.1 molar ki was required for complete inactivation of atpase and ... | 1992 | 16668845 |
| comparison of the outer and inner epidermis : inhibition of auxin-induced elongation of maize coleoptiles by glucan antibodies. | polyclonal antibodies, raised against beta-d-glucans prepared from oat (avena sativa l.) caryopses, cross-reacted specifically with (1-->3),(1-->4)-beta-d-glucans when challenged in a dot blot analysis of related polymers bound to a cellulose thin layer chromatography plate. the antibodies suppressed indoleacetic acid (iaa)-induced elongation of segments from maize (zea mays l.) coleoptiles when the outer surface was abraded. however, iaa-induced elongation of nonabraded segments or segments wit ... | 1992 | 16668791 |
| relationship between electron transport across the plasmalemma and a ph decrease in the bulk medium. | the hypothesis is tested that acidification of the bulk medium during transplasmalemma electron transport to ferricyanide is due solely to a requirement for charge balance. according to this hypothesis, reduction of the trivalent anion, ferricyanide, to the tetravalent anion, ferrocyanide, results in a charge difference that is balanced by protons. a coulometric device is used that rapidly and efficiently reoxidizes ferrocyanide to ferricyanide, thus maintaining a constant charge in the bulk med ... | 1992 | 16668776 |
| 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 |
| novel light-regulated chloroplast thylakoid membrane protein. | a 64 kilodalton chloroplast membrane polypeptide was dependent on growth irradiance with 10-fold greater quantities of the protein present in barley (hordeum vulgare) grown under 500 micromoles of photons per square meter per second compared with growth at 50 micromoles per square meter per second. the concentration of the protein was sensitive to changes in irradiance, with a slow time course for the response (days) similar to other reported light acclimation processes. the polypeptide also was ... | 1992 | 16668749 |
| k channels are responsible for an inwardly rectifying current in the plasma membrane of mesophyll protoplasts of avena sativa. | in whole-cell recording, the conductance of the plasma membrane of protoplasts isolated from mesophyll cells of leaves of oat (avena sativa) was greater for inward than outward current. the inward current in both the whole-cell mode and with isolated patches was dependent on [k(+)](o). when the membrane voltage was more positive than -50 millivolts, the membrane conductance in the whole-cell mode was low, and k(+) channels in cell-attached or outside-out patches had a low probability of being op ... | 1992 | 16668731 |
| proton efflux from oat coleoptile cells and exchange with wall calcium after iaa or fusicoccin treatment. | elongation growth of plant cells occurs by stretching of cell walls under turgor pressure when intermolecular bonds in the walls are temporarily loosened. the acid-growth theory predicts that wall loosening is the result of wall acidification because treatments (including iaa and fusicoccin) that cause lowered wall ph cause elongation. however, conclusive evidence that iaa primarily reduces wall ph has been lacking. calcium has been reported to stiffen the cell walls. we have used a microelectro ... | 1993 | 24178494 |
| 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 |
| mapping of beta-tubulin genomic sequences in hexaploid oat (arena sativa l.). | the allohexaploid nature of avena sativa l. (2n=6x=42) and the availability of aneuploid lines was exploited in designing a strategy for mapping beta-tubulin sequences in the oat genome. evidence for a minimum of eight beta-tubulin genes was obtained by southern-blot analysis. three betatubulin sequences were localized to chromosomes using dna from monosomic and nullisomic lines in the variety sun ii. one sequence was localized to the chromosome missing in nullisome i. two other sequences were m ... | 1993 | 24193393 |
| isozyme variation in germplasm accessions of the wild oat avena sterilis l. | optimal exploitation of crop genetic resources requires a knowledge of the range and structure of the variation present in the gene pool of interest. avena sterilis l., the cultivated oat progenitor, contains a store of genetic diversity that is readily accessible to the oat breeder. the objectives of the present paper were: (1) to evaluate isozyme polymorphisms in a sample of a. sterilis accessions from the u.s. national small grains collection, (2) to analyze the distribution of isozyme divers ... | 1993 | 24193383 |
| spatial distribution of three phytochromes in dark- and light-grown avena sativa l. | we have addressed two issues regarding the spatial distribution of three phytochromes in 3-d-old oat (avena sativa l.) seedlings. three monoclonal antibodies, go-4, go-7 and oat-22, were used as probes. each antibody detects only one of the phytochromes. the first issue is whether any of the phytochromes might be membrane-bound. to address this issue the abundance of each phytochrome in extracts prepared with either a detergent-free or a detergent-containing buffer was compared by immunoblot ass ... | 1993 | 24178496 |