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H Nohara

Publications and source records attributed to H Nohara.

51 records · Page 3Linked to original sources
PubMed1987

Production of chemotactic factor for lymphocyte by digestion of IgG with a highly purified polymorphonuclear leukocyte neutral thiol proteinase.

In the present study, we purified a neutral thiol proteinase from dog PMN leukocytes and indicated that the proteinase elaborated the chemotactic factor for lymphocytes by cleavage of IgG. The neutral thiol proteinase was purified about 744-fold by ion-exchange chromatographies and affinity chromatography, and the final preparation was over 70% pure. After incubation of dog IgG with the proteinase, three distinct protein peaks were seen by the gel filtration on Sephadex G-200. Only the third peak, perhaps a dialyzable peptide, showed a significant chemotactic activity for dog lymphocytes.

Animals↗
PubMed1985

Purification of a cytosolic factor from rat liver that stimulates transcription in isolated nuclei and its action on purified RNA polymerase II-DNA system.

A cytosolic factor that stimulates transcription in isolated nuclei was purified approximately 4000-fold to near homogeneity from rat liver. The molecular weight of the factor was determined as 47 000 by SDS-polyacrylamide gel electrophoresis. The factor had no detectable deoxyribonuclease and protease activity but showed ribonuclease inhibitor activity. The factor could stimulate transcription in isolated nuclei by 50% at about 3.0 ng and the maximal stimulation was about 100%. When [gamma-S]ATP and [gamma-S]GTP were included in the reaction, the factor stimulated the synthesis of RNA which was able to bind to a mercury-Sepharose column and about 80% of the bound RNA was sensitive to a low concentration of alpha-amanitin. When heparin was added before initiation to preincubation mixture containing RNA polymerases II and DNA, a small but definite incorporation of [14C]UTP was observed. The factor alone had no stimulatory effect on the heparin-resistant incorporation of [14C]UTP but, in the presence of two rat liver nuclear fractions, phosphocellulose 0.5 and 1 M KCl step fractions, could stimulate the incorporation above the level with the combination of the two nuclear fractions. Antibody raised against the factor inhibited accurate transcription from the adenovirus 2 major late promoter in a nuclear lysate from Ehrlich ascites tumor cells, and the inhibition was neutralized by the factor.

Animals↗
PubMed1982

Differential response of type I and type II cyclic AMP-dependent protein kinases in submandibular gland of isoproterenol-treated rats.

The cytosolic protein kinase isozymes were studied in relation to the secretion of saliva and the proliferative process induced by isoproterenol. At the same time as salivary secretion began, cytosolic protein kinase was activated and, in the absence of cyclic AMP, increased to a maximum level at 10 min after administration of the drug. The active state of the enzyme was maintained for 1-2 h. Chromatographic analysis of the cytosol enzyme revealed that in an activated state type II kinase easily dissociates into the catalytic and regulatory subunits while type I kinase hardly dissociates. Thus we conclude that type I kinase, at least in submandibular gland, is less dissociable in the presence of cyclic AMP than type II kinase but highly active in a ternary complex (R2-4 cAMP-C2). The presence of cyclic AMP-independent protein kinase, which co-chromatographed with protein kinase II, was demonstrated by use of a heat-stable inhibitor from bovine muscle, which totally inhibited the cyclic AMP-dependent enzymes, but stimulated the cyclic AMP-independent protein kinase. The level of protein kinase I decreased to its lowest value, about half that of the control value, at 10 h after isoproterenol injection and then increased slightly at 15 h, whereas type II kinase remained virtually unchanged, suggesting that the two protein kinase isozymes are independently regulated in the proliferating cells.

Animals↗