Publications

effects of indoleacetic acid on dictyosomes of apical and expanding cells of oat coleoptiles.	we found that the auxin-induced growth is mediated through the activation of the dictyosomes (collectively, the golgi apparatus). incubation of oat (avena sativa) coleoptile segments in indoleacetic acid-sucrose-phosphate buffer changes significantly the number of dictyosomes in the expanding cells. a further indication of auxin enhancement of dictyosome activity is a decrease in dictyosomal cisternae (flattened membranous sacs) number. this decrease occurred after 6 minutes of incubation in aux ...	1974	16658863
concentrations of indole-3-acetic acid and its esters in avena and zea.	an isotope-dilution method has been developed for the assay of free indole-3-acetic acid and ester indole-3-acetic acid as measured by indole-3-acetic acid liberated by mild alkaline hydrolysis. application of this method to seedlings of avena sativa and zea mays indicates the upper limit of free indole-3-acetic acid in avena to be about 16 mug per kg and in zea, about 24 mug. the amount of 1 n alkali-labile indole-3-acetic acid in zea is about 330 mug per kg and there is very little 1 n alkali- ...	1974	16658870
effect of red light on coleoptile growth.	the effects of red light in reducing the growth of the oat (avena sativa l.) coleoptile and the synthesis of auxin in the coleoptile tip are detectable 2 hours after treatment and become more pronounced with time. when the coleoptile tip is supplied with additional tryptophan the synthesis of auxin is doubled both in darkness and when exposed to red light. treatment of the tip with gibberellic acid or pyridoxal phosphate overcomes the reduction of auxin synthesis caused by red light. the uptake ...	1974	16658875
the metabolism of oat leaves during senescence: i. respiration, carbohydrate metabolism, and the action of cytokinins.	when the detached first leaves of green or etiolated oat (avena sativa cv. victory) seedlings senesce in the dark, their oxygen consumption shows a large increase, beginning after 24 hours and reaching a peak of up to 2.5 times the initial rate by the 3rd day. this effect takes place while the chlorophyll of green leaves, or the carotenoid of etiolated leaves, is steadily decreasing. kinetin, at a concentration which inhibits the decrease in pigment, completely prevents the respiratory rise; ins ...	1974	16658877
iron requirement and iron uptake from various iron compounds by different plant species.	the fe requirements of four monocotyledonous plant species (avena sativa l., triticum aestivum l., oryza sativa l., zea mays l.) and of three dicotyledonous species (lycopersicum esculentum mill., cucumis sativus l., glycine maxima (l.) merr.) in hydroponic cultures were ascertained. fe was given as nafe-eddha chelate (fe ethylenediamine di (o-hydroxyphenylacetate). i found that the monocotyledonous species required a substantially higher fe concentration in the nutrient solution in order to att ...	1974	16658933
effect of ph and auxin on chloride uptake into avena coleoptile cells.	the effect of ph on (36)cl(-) movement into coleoptile cells (avena sativa l. cv. garry) was investigated and compared with effects of indoleacetic acid. (36)cl(-) uptake, but not efflux, is stimulated when coleoptile sections are placed in media adjusted to ph levels from 5 to 3 after a preincubation period at ph 6.5. the enhancement is seen within 2 minutes, is not correlated with growth, and is completely erased by respiratory inhibitors. in comparison to the acid-induced stimulation, the sti ...	1974	16658985
multiple forms of invertase in developing oat internodes.	three different invertases are found in the developing internodes of oat (avena sativa cv. victory). two soluble invertases (i and ii) are separable on diethylaminoethylcellulose and sephadex columns. they are further distinguished by their kinetic constants, heat stability, and differences in stability and apparent activity optima in response to ph treatments. relative activities of the two soluble isozymes change considerably during the developmental stages examined. invertase i activity rises ...	1975	16659014
plasma membrane adenosine triphosphatase of oat roots: activation and inhibition by mg and atp.	atpase activity of plasma membrane vesicles isolated from oat (avena sativa l. cv. goodfield) roots was examined in the presence of various concentrations of mgcl(2) and atp. a mg(2+): atp ratio of about 1 was required for maximal activity regardless of the concentrations used; the optimum concentration for both mg(2+) and atp was 9 mm. based on the atpase activity at different concentrations of complexed mg.atp and free atp, it is concluded that mg.atp is the true substrate of this enzyme.under ...	1975	16659034
phytochrome characterization by rabbit antiserum against high molecular weight phytochrome.	both small and large sizes of phytochrome purified from garry oat (avena sativa l. ev. garry) as well as large phytochrome purified from newton oat (a. sativa l. cv. newton), rye (secale cereale l. cv. balbo), barley (hordeum vulgare l. cv. harrison), and pea (pisum sativum l. cv. alaska) seedlings are characterized by a specific antiserum against large garry oat phytochrome. a spur is observed by double diffusion assay against large and small garry oat phytochrome indicating only partial identi ...	1975	16659052
immunological and physical characterization of the products of phytochrome proteolysis.	the relationship between high molecular weight (large) and low molecular weight (small) forms of phytochrome has been shown earlier to be one of proteolysis. the products of such proteolysis are characterized here by chromatography through bio-gel p-200 using specific antiphytochrome sera as an assay system. degradation of large oat (avena sativa l. cv. garry) phytochrome as phytochrome, red-absorbing form, phytochrome, far red-absorbing form, or under cycling conditions in crude preparations co ...	1975	16659053
studies on the presence of adenosine cyclic 3':5'-monophosphate in oat coleoptiles.	the incorporation of adenosine-8-(14)c into adenosine cyclic 3':5'-monophosphate in coleoptile-first leaf segments of avena sativa l. was investigated. homogenates of segments incubated in adenosine-8-(14)c for either 4 or 10 hours were partially purified by thin layer chromatography followed by paper electrophoresis. a radioactive fraction, less than 0.06% of the (14)c present in the original homogenate, migrated as adenosine cyclic 3':5'-monophosphate during electrophoresis. upon treatment wit ...	1975	16659080
the metabolism of oat leaves during senescence: iii. the senescence of isolated chloroplasts.	the changes in chlorophyll and protein in senescing chloroplasts isolated from the first leaves of 7-day-old oat (avena sativa) seedlings have been investigated. in darkness the chlorophyll in these plastids is highly stable, losing only 5 to 10% of its content after 7 days at 26 c. this result contrasts with the behavior of chlorophyll in intact leaves, in which about 80% of the pigment would have disappeared in that time. the protein is less stable than the chlorophyll, though more stable than ...	1975	16659176
regulation of cell wall synthesis in avena stem segments by gibberellic acid.	gibberellic acid induces (a) increased elongation of avena sativa stem segments, (b) increased formation of cell wall material, measured on the basis of dry weight, and (c) increased incorporation of (14)c-glucose into all fractions of the cell wall material. this increased incorporation of radioactivity correlates well with increased formation of cell wall material and shows a time-course pattern similar to the time course of the elongation response. approximately one hour after the application ...	1975	16659206
evidence for ammonium-dependent de novo synthesis of glutamate dehydrogenase in detached oat leaves.	glutamate dehydrogenase becomes density labeled through the incorporation of deuterium and (15)n when detached oat leaves (avena sativa var. fulghum) are incubated in the presence of ammonia. the enzyme has been isolated by means of deae-cellulose chromatography, ammonium sulfate precipitation, isopycnic equilibrium centrifugation, and disc electrophoresis from leaves fed l-methionine-(35)s. radioactivity is incorporated into isozyme 1 of glutamate dehydrogenase, whereas isozyme 2, detected only ...	1975	16659411
attempts to detect cyclic adenosine 3':5'-monophosphate in higher plants by three assay methods.	endogenous levels of cyclic adenosine-3':5'-monophosphate in coleoptile first leaf segments of oat (avena sativa l.), potato (solanum tuberosum l.) tubers, tobacco (nicotiana tabacum l.) callus, and germinating seeds of lettuce (lactuca sativa l.) were measured with a modified gilman binding assay and a protein kinase activation assay. the incorporation of adenosine-8-(14)c into compounds with properties similar to those of cyclic amp was also measured in studies with germinating lettuce seeds. ...	1976	16659419
lack of influence of phytochrome on membrane permeability to tritiated water.	the water permeability of tissues was investigated by measuring the efflux of (3)hho from previously loaded (in darkness) etiolated bean buds (phaseolus vulgaris l. var. red kidney), pea epicotyl segments (pisum sativum l. var. alaska), and oat coleoptile segments (avena sativa l. var. garry). red light, far red light, or darkness was applied at the time of transfer of tissue from labeled to unlabeled medium. there were no effects of light on half-time for efflux or on the maximum level of radio ...	1976	16659447
characterization of passive ion transport in plasma membrane vesicles of oat roots.	the passive influx and efflux of inorganic ions across plasma membrane vesicles purified from extracts of avena sativa roots were investigated. uptake was measured by incubating the vesicles in a radioisotope for various times. the "loaded" vesicles were separated from the external solution by gel filtration. efflux was measured by dialyzing the preloaded vesicles.ion transport was differentiated from superficial ion binding by (a) the time course of association of radioisotope with the vesicles ...	1976	16659668
red light-enhanced phytochrome pelletability: re-examination and further characterization.	red light-enhanced pelletability of phytochrome was observed in extracts of all 11 plants tested: avena sativa l., secale cereale l., zea mays l., cucurbita pepo l., sinapis alba l., pisum sativum l., helianthus anuus l., raphanus sativus l., glycine max (l.) merr., phaseolus vulgaris l., and lupinus albus l. this enhanced pelletability was observed in all 11 plants following in situ irradiation (in vivo binding) but only in sinapis and cucurbita after irradiation of crude extracts (in vitro bin ...	1976	16659745
metabolism of indole-3-acetic acid: iv. biological properties of amino acid conjugates.	the biological activity of 20 l-alpha-amino acid conjugates of indole-3-acetic acid (iaa) to stimulate cell elongation of avena sativa coleoptile sections and to stimulate growth of soybean cotyledon tissue cultures has been examined at concentrations of 10(-4) to 10(-7)m. in the avena coleoptile test, most of the amino acid conjugates stimulated elongation. several of the conjugates stimulated as much elongation as iaa but their half-maximum concentrations tended to be higher. some of the more ...	1977	16659795
long distance translocation of sucrose, serine, leucine, lysine, and carbon dioxide assimilates: ii. oats.	to establish whether several amino acids were equally able to enter the phloem of oat (avena sativa l.) plants and be transported, several (14)c-labeled amino acids were applied individually to an abraded spot on a fully expanded source leaf. the base of an immature sink leaf was monitored with a gm tube for time and rate of arrival of radioactivity. transport of (14)c-sucrose and (14)co(2) assimilates was measured for a comparison. the applied l-serine, l-lysine, and l-leucine, as well as sucro ...	1977	16659821
superoxide dismutases: i. occurrence in higher plants.	shoots, roots, and seeds of corn (zea mays l., cv. michigan 500), oats (avena sativa l., cv. au sable), and peas (pisum sativum l., cv. wando) were analyzed for their superoxide dismutase content using a photochemical assay system consisting of methionine, riboflavin, and p-nitro blue tetrazolium. the enzyme is present in the shoots, roots, and seeds of the three species. on a dry weight basis, shoots contain more enzyme than roots. in seeds, the enzyme is present in both the embryo and the stor ...	1977	16659839
superoxide dismutases: ii. purification and quantitative relationship with water-soluble protein in seedlings.	superoxide dismutase was purified from pea (pisum sativum l., cv. wando) seeds and corn (zea mays l., cv. michigan 500) seedlings. the purified pea enzyme eluting as a single peak from gel exclusion chromatography columns contained the three electrophoretically distinct bands of superoxide dismutase characterizing the crude extract. the purified corn enzyme eluted as the same peak as the pea enzyme, and contained five of the seven active bands found in the crude extract. the similar molecular we ...	1977	16659840
effects of osmotic shock on some membrane-regulated events of oat coleoptile cells.	oat coleoptile sections (avena sativa l. cv. "garry") were osmotically shocked with 0.5 m mannitol followed by 1 mm na-phosphate (ph 6.4) at 4 c. this treatment reduced uptake of alpha-aminoisobutyric acid, 3-o-methyl glucose, and leucine by 75 to 90% but inhibited (36)cl(-) uptake only 30%. some recovery was observed 1 to 3 hours later. respiration rates were unaffected by osmotic shock and protein synthesis was reduced 11%.osmotic shock also stimulated efflux of alpha-aminoisobutyric acid and ...	1977	16659852
osmotic shock inhibits auxin-stimulated acidification and growth.	cells of oat coleoptiles (avena sativa l. cv. "garry") have been osmotically shocked in order to observe the effect of alterations of the plasma membrane on some auxin responses. when coleoptile sections were treated sequentially with 0.5 m mannitol and 1 mm na-phosphate (ph 6.4) at 4 c, polar auxin transport and acidification by 1 mm cacl(2) were unaffected, but auxin-stimulated acidification and growth were eliminated. shock treatment also had no effect on acid-stimulated growth or on freezing ...	1977	16659853
metabolism of oat leaves during senescence: v. senescence in light.	a comparison has been made of the progress of senescence in the first leaf of 7-day-old oat plants (avena sativa cv. victory) in darkness and in white light. light delays the senescence, and intensities not over 100 to 200 ft-c (1000-2000 lux) suffice for the maximum effect. in such intensities, chlorophyll loss and amino acid liberation still go on in detached leaves at one-third to one-half the rate observed in darkness; however, when the leaves are attached to the plant, the loss of chlorophy ...	1977	16659871
phytochrome-controlled hydrogen ion excretion by avena coleoptiles.	a red light-induced, far red reversible stimulation of proton efflux from apical segments of etiolated avena sativa l. cv. victory coleoptiles was observed. the acidification responses to red light and also to auxin were not the consequence of respired co(2). the response to red light was strongly inhibited by cycloheximide and carbonyl cyanide, m-chlorophenyl hydrazone, but mannitol had a stimulatory effect. red light and auxin applied together yielded a greater than additive response, in compa ...	1977	16659904
selectivity of alkali cation influx across the plasma membrane of oat roots: cation specificity of the plasma membrane atpase.	influx of alkali cations (li(+), na(+), k(+), rb(+), cs(+)) across plasma membranes of cells of excised roots of avena sativa cv. goodfield was selective, but different, in the absence and in the presence of 1 mm caso(4). ca(2+) reduced the influx rates of all of the alkali cations-especially na(+) and li(+). transport selectivity changed as the external concentrations of the alkali cations increased.plasma membrane atpase, purified from avena sativa roots, was differentially stimulated by alkal ...	1977	16659910
formation of n-acetylglutamate by extracts of higher plants.	the enzymic synthesis of n-acetylglutamate was studied in extracts of higher plant tissues, especially in sugar beet leaves (beta vulgaris l.). sugar beet leaves had an enzyme that transferred the acetyl group either from acetyl-coa or from n(2)-acetylornithine to glutamate. the enzyme was so unstable that special precautions were necessary for its detection and appreciable purification was impossible. the km values were 2.5 and 0.025 mm for acetyl-coa and n(2)-acetylornithine, respectively. the ...	1977	16659918
cell-free synthesis of globulin by developing oat (avena sativa l.) seeds.	the primary storage protein synthesized during oat (avena sativa l.) groat development is a globulin. polysomes were isolated from oat groats 12 days after anthesis. these polysomes directed the incorporation of radioactive amino acids into protein in a cell-free protein synthesis system containing wheat germ supernatant. the mg(2+) optimum was 4 mm, the ph optimum was 6-8, and the amount of amino acid incorporation depended on polysome concentration. incorporation of amino acids was linear for ...	1977	16659952
occurrence of a high temperature sensitivity of chloroplast ribosome formation in several higher plants.	a specific high temperature-induced deficiency of chloroplast ribosome formation, as indicated by the absence of chloroplast rrna, has been observed in the leaves of light- or dark-grown seedlings of avena sativa l., hordeum vulgare l., and triticum aestivum l. at certain temperatures between 28 and 34 c. while the growth of the leaves (size, morphology, total amino nitrogen content) was little affected by the elevated temperature, chlorophyll accumulation was strongly inhibited, amounting to on ...	1977	16659957
proteases of senescing oat leaves: i. purification and general properties.	two proteases active in the senescing first leaves of oat seedlings (avena sativa cv. victory) have been purified approximately 500-fold by a combination of ammonium sulfate precipitation, affinity chromatography on hemoglobin-sepharose, and ion exchange chromatography on deae-sephadex. the enzymes show ph optima of 4.2 and 6.6 with denatured hemoglobin as substrate, and the molecular weights of both are about 76,000. their optimum temperatures are close to 50 c. small amounts of a third enzyme, ...	1977	16659993
chloroplast phosphofructokinase: i. proof of phosphofructokinase activity in chloroplasts.	ammonium sulfate fractionation of an extract from the leaves of spinach (spinacia oleracea l.) produced two fractions of phosphofructokinase activity, the first stimulated by inorganic phosphate and the second inhibited by inorganic phosphate. only the second fraction was obtained from similar treatment of an extract of isolated spinach chloroplasts. the two fractions differed distinctly with respect to kinetics for the substrate fructose 6-phosphate. evidence for these two types of phosphofruct ...	1977	16660078
effects of indoleacetic acid on the quantity of mitochondria, microbodies, and plastids in the apical and expanding cells of dark-grown oat coleoptiles.	we determined the number of mitochondria, microbodies, and plastids in dark-grown oat (avena sativa) coleoptiles following incubation in indoleacetic acid (iaa) for a period of 60 minutes at 6-minute intervals. in the apical outer epidermis of coleoptiles, the mitochondria increased from 31.4 to 35 per cell section with a 6-minute incubation in iaa, and this trend persisted over the 60-minute incubation. neither the microbodies, plastids, nor the dicytosomes (gawlik and miller 1974 plant physiol ...	1977	16660086
responses of enzymically isolated aleurone cells of oat to gibberellin a(3).	oat (avena sativa l.) aleurone layer cells (spheroplasts) were isolated by maceration of the aleurone layer with a mixture of commercially available cellulase and pectinase. about 20% of the cells present in intact layers were released as spheroplasts and 79 +/- 9% of the spheroplast population was viable as judged by methylene blue staining. the spheroplasts became disorganized in solutions containing less than 0.4 md-mannitol. when the spheroplasts were incubated for 48 hours, total activities ...	1977	16660114
isolation and purification of an alpha-mannosidase from coleoptiles of avena sativa.	an alpha-mannosidase has been purified from the coleoptiles of avena sativa l. var. segrehavre. the enzyme, which is tightly associated with the cell wall, was solubilized with 3 m licl. the purification involves precipitation with (nh(4))(2)so(4), gel filtration, ion exchange chromatography, and isoelectric focusing. the enzyme appears homogeneous when chromatographed on disc gels and on isoelectric focusing gels. the enzyme runs as a single protein of constant specific activity when chromatogr ...	1977	16660119
occurrence and properties of polygalacturonase in avena and other plants.	polygalacturonase activity has been detected in a number of plants including seedlings of phaseolus vulgaris, zea mays, avena sativa, and pisum sativum. particular emphasis was placed on characterizing the enzyme from oat seedlings. this enzyme is solubilized by 0.2 m nacl, and its activity is highest near the apical tips of oat coleoptiles. it has a ph optimum between 5 and 5.5 and is activated by ca(2+), with an optimal concentration of 0.4 mm. cd(2+) also activates the enzyme but less effecti ...	1977	16660135
stabilization of oat leaf protoplasts through polyamine-mediated inhibition of senescence.	protoplasts isolated from avena sativa l. leaves undergo progressive senescence when incubated aseptically in 0.6 m mannitol with or without added nutrients. this senescence is manifested by morphological deterioration and ultimate lysis of protoplasts, by a decrease in incorporation of [(3)h]uridine and [(3)h]leucine into macromolecules, and by a sharp increase in ribonuclease activity.the presence in the incubation medium of l-arginine, l-lysine, certain polyamines related to these amino acids ...	1977	16660139
beta-d-glucan of avena coleoptile cell walls.	a specific glucanase was used to liberate a noncellulosic beta-d-glucan from isolated cell walls of avena sativa coleoptile tissue. cell walls of this tissue contain as much as 7 to 9 mg of glucan/100 mg of dry wall. because of the specific action pattern of the enzyme, a linkage sequence of.. 1 --> 4 glc 1 --> 3 glc 1 --> 4 glc.. is indicated and the predominance of trisaccharide and tetrasaccharide as hydrolytic products suggests a rather regular repeating pattern in the polysaccharide. the tr ...	1977	16660149
comparison of three methods for measuring electrical resistances of plant cell membranes.	the reliability of two different membrane resistance-measuring methods that use a single intracellular microelectrode was tested against a conventional method that uses two intracellular microelectrodes. the first single-electrode method used a single square current pulse and required a constant microelectrode resistance. this method was unreliable because the electrode resistance changed markedly on cell penetration and changed with time within the cell. the second method used a high frequency ...	1977	16660164
proteases of senescing oat leaves: ii. reaction to substrates and inhibitors.	two proteases isolated from senescent oat (avena sativa) leaves have been subjected to further study. one of these, an acid protease active at ph 4.2, is inhibited by phenylmethylsulfonyl fluoride (pmsf) but not by iodoacetamide (iac). the other, active at ph 6.6, is inhibited by both pmsf and iac. these results, together with previously reported evidence that mercaptoethanol stimulates the activity of only the neutral protease, are taken to indicate that the acid protease is probably of the ser ...	1978	16660324
alkylguanidine inhibition of ion absorption in oat roots.	the effect of various alkylguanidines on ion absorption and energy metabolism in oat (avena sativa cv. goodfield) roots has been investigated. of several alkylguanidines tested, octylguanidine was the most effective inhibitor of both k(+) and cl(-) absorption by excised roots. at 225 mum octylguanidine, the transport of both ions was inhibited within 60 seconds and to a similar extent. octylguanidine inhibited mitochondrial oxidative phosphorylation and mitochondrial adenosine 5'-triphosphatase ...	1978	16660414
evidence for amino acid-h co-transport in oat coleoptiles.	microelectrode and tracer techniques were used to test for possible amino acid-h(+) co-transport in coleoptiles of avena sativa l. cv. "garry." the amino acid analogue alpha-aminoisobutyric acid (aib) caused transient depolarization of the membrane potential. the absolute magnitude of the maximum depolarization was affected by the same factors that affected aib transport. both increased with higher concentrations of aib, increased with higher acidities in the medium, and were enhanced by indolea ...	1978	16660429
dual mechanisms in polyamine-mediated control of ribonuclease activity in oat leaf protoplasts.	dibasic amino acids and polyamines added to oat (avena sativa l.) leaf protoplast isolation media decrease the rnase activity of extracted protoplasts relative to controls. this effect, which is manifested even when the added polyamine is removed by exhaustive dialysis prior to assay, is due to a prevention of the rise in rnase activity which usually follows protoplast isolation. polyamines, but not dibasic amino acids, also decrease rnase activity in vitro. this in vitro effect seems to result ...	1978	16660458
cadmium alteration of root physiology and potassium ion fluxes.	segments of oat (avena sativa l.) roots which had been exposed to 1 millimolar cdso(4) in quarter-strength hoagland no. 1 solution exhibited decreased respiratory rates, atp levels, membrane-bound atpase activity, and reduced k(+) fluxes. respiration and atp levels were decreased after a 2-hour treatment with 1 millimolar cdso(4) to 65 and 75%, respectively, of control rates. a membrane-bound, mg(2+)-dependent, k(+)-stimulated acid atpase was rapidly inhibited to 12% of control activity in the p ...	1978	16660477
regulation of glucose metabolism and cell wall synthesis in avena stem segments by gibberellic acid.	gibberellic acid (ga) stimulated both the elongation of avena sativa stem segments and increased synthesis of cell wall material. the effects of ga on glucose metabolism, as related to cell wall synthesis, have been investigated in order to find specific events regulated by ga. ga caused a decline in the levels of glucose, glucose 6-phosphate, and fructose 6-phosphate if exogenous sugar was not supplied to the segments, whereas the hormone caused no change in the levels of glucose 6-phosphate, f ...	1978	16660524
effect of abscisic acid on the gain of the feedback loop involving carbon dioxide and stomata.	gains of the feedback loops involving intercellular co(2) concentration on one hand, and co(2) assimilation and stomata on the other (= assimilation loop with gain [g(a)] and conductance loop with gain [g(g)]) were determined in detached leaves of amaranthus powelli s. wats., avena sativa l., gossypium hirsutum l., xanthium strumarium l., and zea mays in the absence and presence of 10(-5)m (+/-) abscisic acid (aba) in the transpiration stream. determinations were made for an ambient co(2) concen ...	1978	16660528
subunit structure and composition of oat seed globulin.	oat (avena sativa l.) seed globulin was extracted from ground caryopses with 1 m nacl, 0.05 m tris(hydroxymethyl)aminoethane (ph 8.5) at room temperature. the globulin had a sedimentation constant of 12.1, and a molecular weight of 322,000, as determined by analytical ultracentrifugation. the globulin could be separated into two major subunits by sodiumdodecyl sulfate polyacrylamide gel electrophoresis. molecular weights of the subunits were 21,700 (alpha) and 31,700 (beta), and they were presen ...	1978	16660548
kinetics of membrane transport during chloroplast development.	in the course of plastid development there are changes in the permeability of the envelope membranes. an investigation of the kinetics of transport with largely uncontaminated and intact etioplast/etiochloroplast preparations from greening avena sativa laminae demonstrates: (a) that etioplasts already possess specific translocators for the transporation of orthophosphate, dihydroxyacetone phosphate, 3-phosphoglycerate ("phosphate translocator"), and dicarboxylic acids ("dicarboxylate translocato ...	1978	16660596
capping structures at the 5'-terminus of polyadenylated ribonucleic acid in avena coleoptiles.	evidence is presented for the occurrence of 5'-terminal capping structures in the polyadenylated rna of oat (avena sativa) coleoptiles. these structures are composed of an inverted terminal nucleoside containing the modified base 7-methylguanine which is joined 5' to 5' with a second (penultimate) nucleoside by means of three phosphate groups in two pyrophosphate linkages. the penultimate nucleoside is joined to the remainder of the rna molecule by a conventional 3',5' phosphodiester bond. a sig ...	1978	16660619
phytochrome destruction: apparent inhibition by ethylene.	phytochrome destruction begins immediately following actinic irradiation of 4-day-old, dark-grown oat (avena sativa l., cv. garry) shoots grown in open containers. when grown in closed containers, otherwise identical oat shoots exhibit a delay of about 40 minutes between irradiation and the onset of destruction. this delay can be attributed to accumulation of ethylene by several criteria, including elimination of the delay by mercuric perchlorate. these data provide an explanation for otherwise ...	1978	16660639
use of lipophilic cations to measure the membrane potential of oat leaf protoplasts.	uptake of the lipophilic cation triphenylmethylphosphonium into mesophyll protoplasts of oat (avena sativa l. cv. "garry") approaches equilibrium at 3 to 4 hours. the resulting external and internal concentrations are then used with the nernst equation to obtain a membrane potential of -62 millivolts, inside negative. potentials calculated in this manner are depolarized by adding 2 mm sodium azide and 50 mum carbonyl cyanide m-chlorophenylhydrazone as well as by increasing the external proton an ...	1978	16660641
red light and auxin effects on rubidium uptake by oat coleoptile and pea epicotyl segments.	apical segments of etiolated oat (avena sativa l. cv. victory) coleoptiles showed enhanced uptake of [(86)rb(+)] when tested 30 minutes after a 5-minute red irradiation. the response was partly reversible by far red light. uptake was sensitive to carbonyl cyanide m-chlorophenyl hydrazone, but not to isotonic mannitol. indoleacetic acid (10(-7) molar) caused a very pronounced and rapid stimulation of uptake. basal coleoptile segments also exhibited a red light-enhanced uptake, but not an effect o ...	1979	16660665
effect of diethylstilbestrol on ion fluxes in oat roots.	effects of diethylstilbestrol (des) on ion fluxes in oat roots (avena sativa l.) were investigated by measuring k(+) and cl(-) absorption and k(+) efflux. des rapidly decreased the absorption of k(+) ((86)rb) and (36)cl(-) by excised roots; 10(-4) molar des inhibited cl(-) absorption in 1 minute and k(+) absorption in 1 to 2 minutes. with a 10-minute incubation period, k(+) and cl(-) absorption were inhibited 50% by 1.1x10(-5) molar and 8.4x10(-6) molar des, respectively. treatment for 3 minutes ...	1979	16660689
inhibition of adenosine triphosphatase activity of the plasma membrane fraction of oat roots by diethylstilbestrol.	diethylstibestrol (des) inhibited noncompetitively the atpase in the plasma membrane fraction from avena sativa l. cv. goodfield roots when assayed in the presence of mgso(4) or mgso(4) plus kcl. in the presence of mgso(4), 7.1x10(-5) molar des inhibited the enzyme 50%; whereas in the presence of mgso(4) and kcl, 1.3x10(-4) molar des was required for the same inhibition. dixon plots indicated that in the presence of mgso(4), one molecule of des bound to one molecule of atpase; however, in the pr ...	1979	16660690
comparison of reductions in adenosine triphosphate content, plasma membrane-associated adenosine triphosphatase activity, and potassium absorption in oat roots by diethylstilbestrol.	the possibility was investigated that diethylstilbestrol (des) inhibits potassium absorption in oat (avena sativa l. cv. goodfield) roots by inhibiting mitochondrial functions in addition to inhibiting the plasma membrane atpase. des at 10(-6) molar stimulated the mitochondrial atpase slightly, but higher concentrations had no effect. oxidative phosphorylation by isolated mitochondria was inhibited 50% by 2.6 x 10(-5) molar des; concentrations of 10(-4) molar or greater were completely inhibitor ...	1979	16660692
short term phytochrome control of oat coleoptile and pea epicotyl growth.	continuous recordings of the effect of light on oat (avena sativa l. cv. victory) coleoptile and pea (pisum sativum l. cv. alaska) epicotyl growth were made. using a single excised coleoptile 10 minutes of red light was found to promote growth after a latent period of 46 minutes. the stimulation was transient and was not far red-reversible. blue and far red light also promoted growth with similar kinetics. the action of continuous red or far red light was similar to that of 10-minute light. the ...	1979	16660744
possible role of volatile fatty acids and abscisic acid in the dormancy of oats.	species of avena differ markedly in their levels of pre- and post-harvest dormancy. these species offer the opportunity of determining if dormancy is related to the endogenous level of growth inhibitor. germinability in two species of differing levels of dormancy, common oat avena sativa l., and wild oat avena fatua l. was assessed as were the contents of abscisic acid and volatile fatty acids of chain length c(6)-c(10). in a. sativa which did not possess postharvest dormancy there was no correl ...	1979	16660807
phytochrome immunoaffinity purification.	we have developed a phytochrome immunoaffinity purification procedure that yields undegraded oat (avena sativa l., cv. garry) phytochrome of greater than 98% purity within 2 hours when starting with a brushite-purified preparation. immunoaffinity-purified phytochrome, except for its greater purity, is indistinguishable from conventionally purified phytochrome by gel exclusion chromatography, isoelectric focusing, and sodium dodecyl sulfate-polyacrylamide gel electrophoresis. we have also used th ...	1979	16660959
cyanide inhibition of acid-induced growth in avena coleoptile segments.	the comparative effects of metabolic inhibitors on acid- and auxininduced growth in oat (avena sativa l. var. victory) coleoptile segments have been examined. acid (ph 4)-induced growth in both peeled and unpeeled segments is inhibited by 1 millimolar kcn when added at the time of acidification. kcn inhibits total acid-induced growth by 59 and 76%, respectively, in peeled and nonpeeled segments during the first 60 minutes. the growth rate of cyanide-treated tissue drops to zero or near zero in b ...	1979	16661034
metabolism of oat leaves during senescence: vi. changes in atp levels.	the atp content of 7-day-old avena sativa leaves during senescence in dark and in light, and after treatment with cytokinins and other reagents, has been determined by the luciferin-luciferase method. special care was taken to avoid decomposition of the atp, and a detailed procedure is presented for atp analysis at the picomole level. preliminary experiments with several inhibitors of photophosphorylation suggest, though not conclusively, that the delaying effect of light on senescence is mediat ...	1980	16661296
isolation and identification of a senescence-promoting substance from wormwood (artemisia absinthium l.).	the senescence-promoting substance of wormwood (artemisia absinthium l.) as detected by the oat (avena sativa l. cv "victory") leaf assay has been identified as (-)-methyl jasmonate, methyl (1s, 2r)-3-oxo-2-(2'-cis-pentenyl)-cyclopentane-1-acetate, by gas-liquid chromatography-mass spectrometry and optical rotatory dispersion. its senescence-promoting effect was much stronger than that of abscisic acid, and even at such a low concentration as 1 to 2.5 micrograms per milliliter, it could complete ...	1980	16661414
influence of anaerobiosis on chlorophyll biosynthesis in greening oat seedlings (avena sativa l.).	the influence of anaerobiosis for 0.5 to 15 hours on the last steps of chlorophyll biosynthesis of etiolated oat seedlings was investigated. phototransformation of protochlorophyllide to chlorophyllide is only slightly reduced and esterification of chlorophyllide is slightly increased by pretreatment under anaerobic conditions. pretreated plants accumulate the geranylgeraniol ester of chlorophyllide rather than the phytol ester. enzymic hydrogenation of the esterifying alcohol geranylgeraniol to ...	1980	16661480
phytochrome pelletability induced by irradiation in vivo: mixing experiments.	samples of irradiated and control avena sativa shoot tissue were homogenized together to determine whether, during homogenization phytochrome from irradiated tissue can bind to the particulate material simultaneously extracted from the control tissue. the level of phytochrome pelletability for such mixed tissue homogenizations is equal to: (a) the values obtained when the extracts from separate homogenizations of the two batches of tissue are mixed and then centrifuged; and (b) the arithmetic me ...	1980	16661550
hormonal regulation of lateral bud (tiller) release in oats (avena sativa l.).	stem segments containing a single node and quiescent lateral bud (tiller) were excised from the bases of oat shoots (cv. ;victory') and used to study the effects of plant hormones on release of lateral buds and development of adventitious root primordia. kinetin (10(-5) and 10(-6) molar) stimulates development of tillers and inhibits development of root primordia, whereas indoleacetic acid (iaa) (10(-5) and 10(-6) molar) causes the reverse effects. abscisic acid strongly inhibits kinetin-induced ...	1980	16661589
phytochrome control of two low-irradiance responses in etiolated oat seedlings.	light-induced coleoptile stimulation and mesocotyl suppression in etiolated avena sativa (cv. lodi) has been quantitated. etiolated seedlings showed the greatest response to light when they were illuminated 48 to 56 hours after imbibition. two low-irradiance photoresponses for each tissue have been described. red light was 10 times more effective than green and 1,000 times more effective than far red light in evoking these responses. the first response, which resulted in a 45% mesocotyl suppress ...	1981	16661745
changes in endogenous gibberellins and the metabolism of [h]ga(4) after geostimulation in shoots of the oat plant (avena sativa).	the recovery from "lodging," or bending over, by shoots of 42-day-old avena sativa plants is controlled primarily by a negatively geotropic differential growth of the lower halves of the p-1 node-pulvinus and the base of the p-1 internode, relative to the upper halves. although geostimulation causes a significant reduction in p-1 internode length, dry matter accumulation in the p-1 node-pulvinus is increased, apparently at the expense of the sheath. recovery to an angle of 30 degrees is associat ...	1981	16661788
characterization of the inhibition of k absorption in oat roots by salicylic acid.	the phenolic compounds salicylic acid (o-hydroxybenzoic acid) and ferulic acid (4-hydroxy-3-methoxycinnamic acid) inhibited k(+) ((86)rb(+)) absorption in excised oat (avena sativa l. cv. goodfield) root tissue. salicylic acid was the most inhibitory. the degree of inhibition was both concentration- and ph-dependent. with decreasing ph, the inhibitory effect of the phenolic increased. during the early stages of incubation, the time required to inhibit k(+) absorption was also ph- and concentrati ...	1981	16662106
pyruvate orthophosphate dikinase from the immature grains of cereal grasses.	pyruvate orthophosphate dikinase has been identified in the green grains of eight cereal grasses, most of which are classified as c(3) plants. the wheat (triticum aestivum l. cv. lerma rojo) grain enzyme was further investigated: activity was low in very young grains, increased to a maximum at about 25 days after anthesis, then returned to a low level as the grain matured. it appeared to be located in the aleurone layer. a procedure was developed for obtaining partially purified preparations of ...	1982	16662187
osmoregulation in the avena coleoptile : control of solute uptake in peeled sections.	peeled avena sativa coleoptile sections (i.e. sections from which the epidermis has been removed) have been used to study the control of solute uptake under conditions where the uptake is not limited by the cuticular barrier. in the presence of 2% sucrose, auxin enhances the rate at which the total osmotic solutes increase, but this appears to be a response to the increased growth rate, inasmuch as the auxin effect is eliminated when growth is inhibited osmotically. when sections are incubated i ...	1982	16662195
sources of ammonium in oat leaves treated with tabtoxin or methionine sulfoximine.	excised 7-day-old oat (avena sativa l. cv. jaycee) leaves were incubated in media containing 7.1 millimolar kno(3) and 0.15 millimolar tabtoxin or 1 millimolar methionine sulfoximine (mso) to investigate the sources of the observed ammonium accumulated. tabtoxin and mso are known inhibitors of glutamine synthetase, the first enzyme in the primary pathway of ammonium assimilation. during a 4- to 6-hour incubation, there was little net change in protein or total amino acid concentration. alanine, ...	1982	16662206
immunopurification and initial characterization of dicotyledonous phytochrome.	antiserum was prepared against proteolytically undegraded phytochrome obtained from etiolated zucchini squash (cucurbita pepo l., cv. black beauty). the antiserum was prepared by injecting into a rabbit immunoprecipitates between zucchini phytochrome and specific antiserum against undegraded oat (avena sativa l., cv. garry) phytochrome. specific antiphytochrome immunoglobulins were purified from this crude serum by an affinity column consisting of conventionally purified undegraded pea phytochro ...	1982	16662209
relation of polyamine synthesis and titer to aging and senescence in oat leaves.	polyamine biosynthesis in senescing leaves of avena sativa l. was measured by determining the activities of arginine decarboxylase (ec 4.1.1.19), ornithine decarboxylase (ec 4.1.1.17) and s-adenosyl-l-methionine decarboxylase (ec 4.1.1.50). polyamine content was also estimated by thin layer chromatography and high performance liquid chromatography. arginine decarboxylase activity decreases progressively in aging attached first leaves and in senescing excised leaves in the dark. conversely, it in ...	1982	16662218
adenylate levels, energy charge, and phosphorylation potential during dark-light and light-dark transition in chloroplasts, mitochondria, and cytosol of mesophyll protoplasts from avena sativa l.	the compartmentation of cellular energy relations during dark-light and light-dark transitions was studied by means of a newly developed technique to fractionate oat (avena sativa l., var. arnold) mesophyll protoplasts. using an improved microgradient system with hydrophobic and hydrophilic layers of increasing density, a pure plastid pellet (up to 90% of total chloroplasts) could be separated from an interphase of only slightly contaminated mitochondria (70 to 80% of total mitochondria), and a ...	1982	16662227
energy coupling in h-amino acid cotransport : atp dependence of the spontaneous electrical repolarization of the cell membranes in oat coleoptiles.	experiments were undertaken in order to test the mechanism of energy coupling for amino acid uptake proposed in the cotransport hypothesis. according to the hypothesis an electrochemical potential difference in h(+) is established by active h(+) extrusion. that potential difference then drives the cotransport of h(+) and amino acids into the cells. application of amino acids to oat (avena sativa var. victory) coleoptiles induced transient depolarizations of the cell membrane electrical potential ...	1982	16662266
evidence for a cl-stimulated mgatpase proton pump in oat root membranes.	the possibility that plant membrane-bound mgatpases may act as electrogenic proton pumps has been investigated. using an oat (avena sativa l. cv. victory) root membrane preparation which is partially enriched in tightly sealed vesicles, we have shown that mgatp stimulates the uptake of the membrane-permeable anion [(14)c]scn(-) by the vesicles; this indicates that an electrical potential (interior positive) is generated across the membrane. both cl(-) ions and the proton ionophore trifluorometho ...	1982	16662299
regulation of h excretion : effects of osmotic shock.	osmotic shock, a 15-minute plasmolysis followed by a 15-minute rehydration in the cold, is a nondestructive technique which inhibits fusicoccin-stimulated h(+) excretion from oat mesophyll cells (avena sativa l.). osmotic shock also causes a loss of intracellular solutes and stimulates h(+) uptake, but osmoregulation can still occur, and enhanced h(+) uptake is observed only at low external ph. it is concluded that osmotic shock interferes directly with the excretion of h(+) rather than affectin ...	1982	16662323
regulation of h excretion : role of protein released by osmotic shock.	when the protoplasts of peeled oat leaf segments (avena sativa l.) expand after a brief plasmolysis (osmotic shock), fusicoccin-enhanced h(+) excretion is reduced and protein is released to the rehydration medium. this shock protein seems to arise from the cell surface, not from the interior of leaky cells or from broken cells, because (a) the protein differs quantitatively and qualitatively from protein of cell homogenates as determined by sodium dodecyl sulfate-polyacrylamide gel electrophores ...	1982	16662324
biological properties of d-amino acid conjugates of 2,4-d.	some d-amino acid (glutamic acid, valine, or leucine) conjugates of 2,4-dichlorophenoxyacetic acid (2,4-d) at 10(-5) molar, stimulated elongation of avena sativa l. var mariner coleoptile sections and growth of soybean (glycine max. l. var amsoy) tissue as much as did the l-amino acid conjugates at 10(-6) molar. the d-methionine conjugate did not stimulate growth of soybean root callus tissue but did stimulate avena elongation. the d-aspartic acid conjugate did not stimulate elongation of avena ...	1982	16662495
the influence of gibberellic acid and temperature on the growth rate of avena sativa stem segments.	a micro-growth measuring technique was used to determine the growth response of stem segments of avena sativa cv. avon to a variety of gibberellic acid (ga(3)) concentrations over a range of incubation temperatures. growth rate varied with ga(3) concentration, the temperature at which the rate was measured, and the growth temperature of the plants prior to excision of the segments. the curves relating segment extension rates to temperature were affected by ga(3) such that the linear portion of t ...	1982	16662529
localization of spin labels in oat leaf protoplasts.	an assay based on light-mediated oxidation was used to determine whether specific spin labels were partitioned throughout the protoplast or retained in the plasmalemma of avena sativa l. cv. garry and park. many classes of spin label were tested, including phospholipids, fatty acid, fatty acid methyl ester, maleimide, iodoacetamide, short chain hydrocarbon, androstane, 2,2,6,6-tetramethyl-4-aminopiperidinooxyl (tempamine) and 2,2,6,6-tetramethylpiperidinooxyl (tempo). all except the phosphotidyl ...	1982	16662553
interaction of nitroxide spin labels with chloroplasts.	chloroplasts isolated from oats eliminated the electron spin resonance (esr) signals from spin labels in white light and partially restored them in far-red light. only the white light-mediated reaction was blocked by 3-(3,4-dichlorophenyl)-1,1-dimethylurea (dcmu). in contrast, oat (avena sativa l. cv. garry and park) leaf mesophyll protoplasts oxidized the spin labels in both white and far-red light, with and without dcmu. light had no obvious effect on spin label motion within chloroplast membr ...	1982	16662554
wound-induced resistance to cellulase in oat leaves.	peeling the epidermis induces the development of resistance to cellulolytic digestion in the mesophyll cell wals of the first leaf of 1- to 3-week-old oat seedlings (avena sativa var. victory). development of resistance occurs between 3 and 11 hours after the abaxial epidermis is peeled from the blade, and is inhibited by actinomycin d (20 micrograms per milliliter) or cycloheximide (1 microgram per milliliter). other methods of wounding (cutting with a razor blade, stabbing with a dissection ne ...	1982	16662575
ethylene as an effector of wound-induced resistance to cellulase in oat leaves.	peeling the abaxial epidermis from oat leaves (avena sativa var. victory) induces the formation of wound ethylene and the development of resistance to cellulolytic digestion of mesophyll cell walls. ethylene release begins between 1 and 2 hours after peeling in the light or dark. aminoethoxyvinylglycine (avg, 0.1 millimolar), cocl(2) (1.0 millimolar), propyl gallate (pg, 1.0 millimolar) or aminooxyacetic acid (aoa, 1.0 millimolar) inhibits, whereas agno(3) stimulates wound ethylene formation. in ...	1982	16662576
does ethylene play a role in the release of lateral buds (tillers) from apical dominance in oats?	the growth of lateral buds (tillers), which are undergoing release from apical dominance, was measured in upright and gravistimulated intact avena sativa l. cv. ;victory' (oat) shoots as well as in isolated avena stem segments treated with kinetin and sucrose. during release, the tiller bud initially shows a slow rate of elongation accompanied by swelling. it is followed by a more rapid rate of elongation. ethylene (c(2)h(4)) production in shoot segments containing a tiller bud was found to occu ...	1982	16662580
localization of phytochrome in oats by electron microscopy.	phytochrome was localized by immunoelectron microscopy in cells of the coleoptile tip of etiolated and irradiated oat (avena sativa l., cv. konata) seedlings. by using ultrathin frozen sections and immunopurified, monospecific antibodies, both the sensitivity and resolution of the immunocytochemical assay were increased. the results with etiolated plants agree with and extend previously published data. a brief red light illumination caused the redistribution of phytochrome from a diffuse to a mo ...	1982	16662591
evidence from studies with acifluorfen for participation of a flavin-cytochrome complex in blue light photoreception for phototropism of oat coleoptiles.	the diphenyl ether acifluorfen enhances the blue light-induced absorbance change in triton x100-solubilized crude membrane preparations from etiolated oat (avena sativa l. cv. lodi) coleoptiles. enhancement of the spectral change is correlated with a change in rate of dark reoxidation of a b-type cytochrome. similar, although smaller, enhancement was obtained with oxyfluorfen, nitrofen, and bifenox. light-minus-dark difference spectra in the presence and absence of acifluorfen, and the dithionit ...	1982	16662593
comparative phytochrome immunochemistry as assayed by antisera against both monocotyledonous and dicotyledonous phytochrome.	preparation and characterization of antisera against lettuce (lactuca sativa l., cv. grand rapids) and pea (pisum sativum l., cv. alaska) phytochrome is described. these antisera, together with previously obtained antisera against zucchini (cucurbita pepo l., cv. black beauty) and oat (avena sativa l., cv. garry) phytochrome, were used to compare by ouchterlony double immunodiffusion phytochrome isolated from etiolated lettuce, pea, bean (phaseolus vulgaris l., cv. taylor horticultural bush), zu ...	1982	16662599
pigment-protein complexes of illuminated etiolated leaves.	photoconversion of protochlorophyllide in etiolated leaves of avena sativa l., var. pennal or peniarth and phaseolus vulgare l., var. ;the prince' results in the sequential appearance of spectrally distinct chlorophyllide complexes (chlide 678, 684, and 672). this paper reports on the generation of similar forms in vitro, under controlled conditions, using well characterized etioplast membranes enriched in the enzyme protochlorophyllide reductase. excess nadp(+) and nadph stabilize complexes rel ...	1982	16662606
light-induced h secretion and the relation to senescence of oat leaves.	when abraded oat (avena sativa l. cv victory) leaf segments are floated on kcl solution, white light causes acidification of the solution external to leaf tissue. the presence of mannitol amplifies the light-induced proton secretion. mature leaves as well as young ones acidify the medium in light, while senescing leaves (after 3 to 4 days incubated in water in the dark) lose the ability to produce this response to light. the decrease in h(+) secretion is already measureable after as little as 30 ...	1982	16662624
effect of vanadate, molybdate, and azide on membrane-associated atpase and soluble phosphatase activities of corn roots.	the effects of vanadate, molybdate, and azide on atp phosphohydrolase (atpase) and acid phosphatase activities of plasma membrane, mitochondrial, and soluble supernatant fractions from corn (zea mays l. wf9 x mo17) roots were investigated. azide (0.1-10 millimolar) was a selective inhibitor of ph 9.0-atpase activity of the mitochondrial fraction, while molybdate (0.01-1.0 millimolar) was a relatively selective inhibitor of acid phosphatase activity in the supernatant fraction. the ph 6.4-atpase ...	1982	16662676
plasma membranes from oats prepared by partition in an aqueous polymer two-phase system : on the use of light-induced cytochrome b reduction as a marker for the plasma membrane.	presumptive plasma membrane fractions have been prepared from oat (avena sativa l. cv. brighton) roots and shoots, respectively, by partition of microsomal fractions in a dextran-polyethylene glycol two-phase system. the plasma membranes had a high affinity for the polyethylene glycol-rich upper phase, whereas membranes from mitochondria and other organelles partitioned in the dextran-rich lower phase or at the interface. thus, relatively pure plasma membranes were obtained by only two partition ...	1982	16662693
correlation between the lipid composition and the responsiveness of avena sativa stem segments to gibberellic acid.	the lipid composition of avena sativa stem segments was manipulated using basf 13-338 (formerly sandoz 9785) and growth temperature, in order to establish whether there were correlations between responsiveness of the tissue to gibberellic acid (ga(3)) and the presence, before hormone treatment, of specific lipid components. high correlations were obtained between ga(3)-induced growth and total phospholipid, individual phospholipids, and fatty acids (except for linolenic acid), total saturated fa ...	1982	16662703
effects of exogenous 1,3-diaminopropane and spermidine on senescence of oat leaves : i. inhibition of protease activity, ethylene production, and chlorophyll loss as related to polyamine content.	excision and dark incubation of oat (avena sativa l., var. victory) leaves cause a sharp increase in protease activity, which precedes chl loss. both these senescence processes are inhibited by exogenously applied 1,3-diaminopropane (dap), which occurs naturally in leaf segments. the inhibition of protease activity is much greater in vivo than in vitro, suggesting inhibition of protease synthesis as well as protease action by dap. chl breakdown in leaves of radish and broccoli, which also senesc ...	1982	16662725
effects of exogenous 1,3-diaminopropane and spermidine on senescence of oat leaves : ii. inhibition of ethylene biosynthesis and possible mode of action.	the effects of the polyamines spermidine and 1,3-diaminopropane on ethylene biosynthesis and chlorophyll (chl) loss were studied in peeled leaves of oat (avena sativa l., var. victory) incubated in the dark. peeling off the epidermal cells induces an increase in 1-aminocyclopropane-1-carboxylate (acc) synthase activity, resulting in an enhanced acc and ethylene formation. both polyamines inhibit ethylene biosynthesis from methionine by inhibiting acc synthase activity and, more effectively, the ...	1982	16662726
synthesis of oat globulin precursors : analogy to legume 11s storage protein synthesisa.	the oat (avena sativa l.) seed globulin was found to be synthesized in vitro as 60,000 to 64,000 dalton precursors. in vivo protein labeling yielded polypeptides of 58,000 to 62,000 daltons, suggesting cleavage of signal sequences from the precursors. further cleavage is apparently required to separate the alpha and beta polypeptide sequences which are known to form disulfide-linked 53,000 to 58,000 dalton species in the (alphabeta)(6) holoprotein. the data are discussed with respect to analogou ...	1982	16662760
localization of phytochrome in oats by electron microscopy.	phytochrome was localized by immunoelectron microscopy in cells of the coleoptile tip of etiolated and irradiated oat (avena sativa l., cv. konata) seedlings. by using ultrathin frozen sections and immunopurified, monospecific antibodies, both the sensitivity and resolution of the immunocytochemical assay were increased. the results with etiolated plants agree with and extend previously published data. a brief red light illumination caused the redistribution of phytochrome from a diffuse to a mo ...	1982	16662762
metabolism of oat leaves during senescence : vii. the interaction of carbon dioxide and other atmospheric gases with light in controlling chlorophyll loss and senescence.	in air largely freed from co(2), senescence of isolated oat (avena sativa cv victory) seedling leaves is no longer prevented by white light; instead, the leaves lose both chlorophyll and protein as rapidly as in the dark. senescence in light is also accelerated in pure o(2), but it is greatly delayed in n(2); 100% n(2) preserves both protein and chlorophyll in light and in darkness. in light in air, most of the compounds tested that had previously been found to delay or inhibit senescence in dar ...	1983	16662800
isolation and characterization of oat aleurone and starchy endosperm protein bodies.	to compare oat (avena sativa l. cv froker) aleurone protein bodies with those of the starchy endosperm, methods were developed to isolate these tissues from mature seeds. aleurone protoplasts were prepared by enzymic digestion and filtration of groat (caryopsis) slices, and starchy endosperm tissue was separated from the aleurone layer by squeezing slices of imbibed groats followed by filtration. protein bodies were isolated from each tissue by sucrose density gradient centrifugation. ultrastruc ...	1983	16662859
anion-sensitive, h-pumping atpase in membrane vesicles from oat roots.	h(+)-pumping atpases were detected in microsomal vesicles of oat (avena sativa l. var lang) roots using [(14)c]methylamine distribution or quinacrine fluorescent quenching. methylamine (mea) accumulation into vesicles and quinacrine quench were specifically dependent on mg,atp. both activities reflected formation of a proton gradient (deltaph) (acid inside) as carbonyl cyanide m-chlorophenylhydrazone, nigericin (in the presence of k(+)), or gramicidin decreased mea uptake or increased quinacrine ...	1983	16662875
putrescine and acid stress : induction of arginine decarboxylase activity and putrescine accumulation by low ph.	incubation of peeled oat avena sativa l. var victory leaf segments on media of ph 5.0 or below leads to a rapid and massive increase in the titer of putrescine while incubation at ph values above 5.0 causes little or no change. the low ph effect is independent of the buffer system employed. putrescine levels rise within 3 hours and reach their peak 8 to 9 hours after acidification. at this time, putrescine titer is eight times greater at ph 3.5 than at 6.0. none of the other polyamines shows a r ...	1983	16662904