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J H Cherry

Publications and source records attributed to J H Cherry.

At least 37 records · Page 2Linked to original sources
PubMed1972

Enhancement of RNA polymerase activity by a factor released by auxin from plasma membrane.

Using recently developed techniques for solubilization of RNA polymerase from soybean chromatin and isolation of plasma membrane fractions from plants we can show the presence of a transcriptional factor specifically released from the membranes by auxin, 2,4-dichlorophenoxyacetic acid. The nonauxin, 3,5-dichlorophenoxyacetic acid, does not release the factor, but subsequent exposure of the membranes to auxin results in its release. Factor activity could not be demonstrated in fractions devoid of plasma membranes. The presence of a regulatory factor for RNA polymerase associated with plant plasma membrane and specifically released by auxin provides a mechanism whereby both rapid growth responses and delayed nuclear changes could be derived from a common auxin receptor site associated with plasma membrane.

Cell Fractionation↗
PubMed1972

Purification and properties of adenosine diphosphoglucose pyrophosphorylase from sweet corn.

A 40-fold purification of adenosine diphosphoglucose pyrophosphorylase from sweet corn (Zea mays var. Golden Beauty) revealed the enzyme to be specific for adenosine triphosphate. The enzyme has an absolute requirement for Mg(2+) and is activated by 3-phosphoglycerate and to a lesser extent by ribose-5-phosphate and fructose-6-phosphate. The apparent Km values of the enzyme for glucose-1-phosphate, adenosine triphosphate, pyrophosphate, and adenosine diphosphoglucose are 1.9 x 10(-4), 3.2 x 10(-5), 3.3 x 10(-5), and 6.2 x 10(-4)m, respectively. Pyrophosphate inhibits adenosine diphosphoglucose synthesis competitively (Ki = 3.8 x 10(-7)m), while orthophosphate and sulfate appear to inhibit the reacion noncompetitively. These results show that the production of this sugar nucleotide can be controlled by the concentration of pyrophosphate.

Journal Article↗
PubMed1971

Isolation of an organ-specific leucyl-tRNA synthetase from soybean seedling.

The leucyl-tRNA synthetase activity from cotyledons of 4-day-old soybean seedlings has been fractionated into three components. One of these exclusively acylates two of the six tRNA(Leu) species present in this tissue. The remaining two enzyme fractions charge the other four tRNA(Leu) species equally well. Soybean hypocotyls appear to contain only the last two enzyme fractions.

Chromatography↗
PubMed1971

Chromatin- and nuclei-directed ribonucleic Acid synthesis in sugar beet root.

The synthesis of RNA by chromatin-bound RNA polymerase prepared from sugar beet (Beta vulgaris) root tissue is completely dependent on the presence of a divalent metal (Mg(2+) or Mn(2+)) and the presence of four ribonucleoside triphosphates. Accumulation of labeled acid-insoluble product is inhibited by the addition of RNase and actinomycin D to the reaction. When beet root slices are washed for 25 hours, chromatin-associated RNA polymerase activity increases 7-fold over that of unwashed tissue. This enzyme activity declines with further washing. DNA template availability, as measured by saturating levels of added Escherichia coli RNA polymerase, was also found to follow a pattern similar to that for RNA polymerase. Nearest neighbor frequencies of the RNA synthesized by chromatin isolated from unwashed and washed tissue are different.Washing tissue in solutions of gibberellic acid and auxin enhances template availability of the isolated chromatin. Experiments with isolated nuclei indicate an effect of these hormones on RNA synthesis.

Journal Article↗
PubMed1971

Effects of gamma irradiation on chromatin activity of sugar beet tissue.

Chromatin-associated RNA polymerase activity increases during washing of sugar beet tissue to a maximum by 20 hours. This increase was inhibited by dosages of gamma irradiation between 50 and 400 krad. Template availability, as measured by saturating levels of added Escherichia coli RNA polymerase, also increased with washing and was inhibited, although to a lesser extent, by the above irradiation dosages. Neither endogenous polymerase activity nor template availability was affected by high dosages (300 krad) in unwashed tissue. Exposure of tissue to irradiation (300 krad) at different times during a 20-hour washing period severely inhibited the development of RNA polymerase activity during the early stages of washing. The inhibition of template availability, however, was independent of time of irradiation. The data presented are discussed in relation to the mechanisms involved in the inhibitory effects of gamma irradiation on RNA production and subsequent protein synthesis.

Journal Article↗
PubMed1971

Enhanced deoxyribonucleic Acid polymerase activity of chromatin from soybean hypocotyls treated with 2,4-dichlorophenoxyacetic Acid.

Chromatin isolated from soybean (Glycine max L., var. Wayne) hypocotyls was capable of catalyzing the polymerization of labeled deoxyribonucleoside triphosphate in the presence of the three other deoxyribonucleoside triphosphates into a trichloroacetic acid-insoluble product. This product was insensitive to base hydrolysis and ribonuclease, but was sensitive to acid hydrolysis and deoxyribonuclease. Chromatin-DNA polymerase required Mg(2+) and all four deoxyribonucleoside triphosphates for maximal activity. Inorganic pyrophosphate and actinomycin D inhibited the polymerase activity, but 2, 4-dichlorophenoxyacetic acid had no effect in vitro. Chromatin from plants previously treated with 2, 4-dichlorophenoxyacetic acid supported a greater level of DNA synthesis than did chromatin from untreated plants.

Journal Article↗
PubMed1970

The Influence of Auxin and Ethylene on Chromatin-directed Ribonucleic Acid Synthesis in Soybean Hypocotyl.

Soybean seedlings treated with ethylene exhibited small increases in ribonucleic acid content in the elongating section of the hypocotyl. Chromatin isolated from the elongating section of ethylene-treated seedlings showed a 35 to 60% increase in the capacity for RNA synthesis. The ethylene-induced response was saturated at 1 microliter/liter of ethylene and was fully expressed after 3 hours. Auxin caused marked accumulation of RNA and DNA in the elongating and basal tissue of the hypocotyl. Chromatin isolated from these auxin-treated tissues showed an 8- to 10- fold increase in RNA synthetic capacity as measured in vitro. Ethylene added with auxin reduced the auxin enhancement of nucleic acid synthesis in the elongating and basal tissues. Both ethylene and auxin treatment of the seedlings inhibited nucleic acid accumulation and chromatin activity in the apical tissue. Ethylene did not appear to mediate the auxin effects on nucleic acid synthesis in soybean hypocotyl with the possible exception of inhibition in the apical tissue.The RNA which was synthesized by chromatin isolated from control and auxin- and ethylene-treated tissues was characterized by nearest neighbor analyses. The nearest neighbor frequencies of the RNA products synthesized by chromatin isolated from auxin- and ethylene-treated hypocotyl tissue were different from each other and different from the control RNA product.Seedlings treated in sealed containers exhibited growth, RNA, and DNA responses, especially to ethylene, different from those of seedlings treated in continuous flow containers.

Journal Article↗
PubMed1970

Increase in indoleacetic Acid oxidase activity of winter wheat by cold treatment and gibberellic Acid.

The activity of indoleacetic acid oxidase increased 10-fold during 40 days of cold treatment of winter wheat seedlings. Puromycin and 6-methyl purine inhibited indoleacetic acid oxidase development in the cold. Addition of gibberellic acid stimulated indoleacetic acid oxidase development during germination at room temperature and during cold treatment. Amo-1618 inhibited indoleacetic acid oxidase development before and during cold treatment. Indoleacetic acid treatment increased indoleacetic acid oxidase activity during germination at room temperature while no significant effect on activity was observed during cold treatment.

Journal Article↗
PubMed1969

Differences in leucyl-transfer rna's and synthetase in soybean seedlings.

Charged leucyl-transfer RNA (leucyl-tRNA) of soybean cotyledons can be fractionated into six radioactive peaks on a Freon column. Four leucyl-tRNA peaks are observed with the homologous hypocotyl system. Hypocotyl synthetase preparations only slightly acylate the other two leucyl-tRNA's (species 5 and 6). Further, leucyl-tRNA(5 and 6) of the hypocotyl are present in small amounts in comparison to the cotyledon. Therefore, the rate-limiting quantities of synthetase and tRNA(5 and 6) obtained from the hypocotyl prevent the detection of these two species of tRNA when a homologous hypocotyl system is used. To measure the relative amounts of hypocotyl tRNA's, the cotyledon synthetase preparation is employed. Preliminary results show that 6-benzyladenine increases the acylation of leucyl-tRNA(5 and 6) and decreases acylation of tRNA(1) in the hypocotyl. Synthetase preparations from cytokinin-treated plants are not significantly affected.

Journal Article↗