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H Misumi

Publications and source records attributed to H Misumi.

48 records · Page 3Linked to original sources
PubMed1982

Separate detection of glucose-6-phosphate dehydrogenase from 6-phosphogluconate dehydrogenase by DEAE-paper chromatography.

Red blood cell lysates were applied to DEAE cellulose paper for detection of glucose-6-phosphate dehydrogenase. Glucose-6-phosphate dehydrogenase (G-6-PD) was separated from 6-phosphogluconate dehydrogenase (6-PGD) by DEAE-cellulose paper-chromatography and their activities were detected on the chromatogram by applying the reaction mixture. The fluorescence of NADPH formed by G-6-PD was not interfered with by 6-PGD activity. This is a sensitive procedure which detects slight loss of G-6-PD in red blood cells and could be applied to the detection of G-6-PD deficiency.

Chromatography, DEAE-Cellulose↗
PubMed1980

Transcription of reconstituted simian virus 40 nucleoprotein complexes.

The regulatory effects of host cellular histones on the transcription of simian virus 40 (SV40) DNA were investigated by using reconstituted and native SV40 nucleoprotein complexes (NPCs). Reconstituted NPCs were prepared from SV40 DNA and the combination fraction of five histones, H1, H2A, H2B, H3, and H4, isolated from the nuclei of permissive (CV-1) or nonpermissive (BALB/c 3T3, rat liver, and calf thymus) cells. Native NPCs were prepared by alkali disruption of purified SV40 virions. Nuclease digestion of these NPCs gave regular patterns of bands similar to those of SV40 NPCs from SV40-infected CV-1 cells, suggesting the presence of a nucleosomal structure. Transcription of NPCs was analyzed in vitro by using Escherichia coli DNA-dependent RNA polymerase. Both histone H1 and the fraction consisting of all five histones inhibited transcription of SV40 DNA by about 90 to 95%. The fraction consisting of four histones lacking H1 reduced the transcription by 30 to 35%, to a level similar to that of transcription with native NPCs. Transcription was inhibited regardless of whether the origin of histones was permissive or nonpermissive cells. Gel electrophoretic patterns of RNA products transcribed from SV40 DNA and reconstituted and native NPCs showed several identical peaks between 13S and 28S. The patterns were identical whether NPCs reconstituted with H1 alone, all five histones, or four histones lacking H1 were used.

DNA, Viral↗
PubMed1979

RNA synthesis in permeable mouse ascites sarcoma cells.

A permeable cell system for studying RNA synthesis was established. Mouse ascites sarcoma cells were made permeable to nucleoside triphosphates and alpha-amanitin by treating with a hypotonic buffer. Separate determinations of endogenous RNA polymerase I, II and III activities in permeable cells were conducted using the different sensitivities of these enzymes to alpha-amanitin. The endogenous activity of RNA polymerase II under optimal conditions was one tenth of total RNA synthetic activity in isolated nuclei, and one third of that in permeable cells. The extremely low ratio of RNA polymerase II activity to total RNA synthetic activity in isolated nuclei was thought to be caused by increase of RNA polymerase I activity and decrease of RNA polymerase II activity. These and other results suggested that RNA synthesis in permeable cells reflects more precisely the in vivo state of RNA synthesis than thatin isolated nuclei. The permeable cell system will provide a useful method for studying the separate activities of RNA polymerases I, II and III in situ.

Amanitins↗
PubMed1979

Effects of some polyamines, polyanions and antitumor drugs on replicative DNA synthesis and unscheduled DNA synthesis in vitro.

The effects of various compounds on replicative DNA synthesis in permeable mouse ascites sarcoma cells and on unscheduled DNA synthesis in permeable cells or in isolated rat liver nuclei were studied. Polyamines such as spermidine, putrescine and cadaverine inhibited replicative DNA synthesis. Unscheduled DNA synthesis was inhibited by spermidine and cadaverine, but slightly stimulated by putrescine at low concentrations. Aurintricarboxylic acid, a low molecular weight polyanion, inhibited both replicative DNA synthesis and unscheduled DNA synthesis. Replicative DNA synthesis was inhibited by heparin, a high molecular weight polyanion, whereas unscheduled DNA synthesis was stimulated at low heparin concentrations. Antitumor drugs such as daunomycin, neocarzinostatin and bleomycin inhibited replicative DNA synthesis. Unscheduled DNA synthesis was inhibited by daunomycin, slightly induced by neocarzinostatin and highly induced by bleomycin. The present system was thought to be useful for studying the separate effects of various drugs on either replicative DNA synthesis or unscheduled DNA synthesis in vitro.

Animals↗
PubMed1979

Characterization of RNA polymerases from Rous sarcoma virus-induced mouse ascites sarcoma cells.

RNA polymerase was extracted from the Schmidt-Ruppin strain of Rous sarcoma virus (SR-RSV)-induced C3H/He mouse ascites sarcoma cells (SR-C3H). RNA polymerase was separated into RNA polymerases I and II by DEAE-Sephadex chromatography. RNA polymerase I was separated into Ia and Ib fractions by phospho-cellulose chromatography. In SR-C3H cells RNA polymerase Ib was the main component of RNA polymerase I. At 0.05--0.1 M ammonium sulphate RNA polymerase I transcribed native DNA most actively, and RNA polymerase II transcribed denatured DNA most actively. Partial digestion of DNA by DNAase I enhanced RNA synthesis by RNA polymerases I and II. At ionic strength over 0.2 M ammonium sulphate, the initiation reaction of RNA polymerases I and II was inhibited. The initiation complexes of RNA polymerases I and II with native DNA were more stable against high salt concentration than with denatured DNA.

Animals↗
PubMed1975

A comparative study of DNA-dependent RNA polymerases from rat ascites hepatoma cell nuclei and from rat liver nuclei.

DNA-dependent RNA polymerases (EC 2.7.7.6) were extracted and partially purified form the nuclei of rat ascites hepatoma cells (AH-130) induced by 4-dimethylaminoazobenzene. The patterns of RNA synthesis and the properties of these enzymes were compared with enzymes from the nuclei of rat liver. The specific activity of RNA polymerase in the homogenate from the nuclei of AH-130 cells was the same as normal rat liver nuclei. RNA polymerase was solubilized from the homogenate at high ionic strength and separated into two forms by DEAE-Sephadex column chromatography. Enzymatic characterization showed that these enzymes corresponded to RNA polymerase I and II. RNA polymerase I more effectively transcribed native DNA than denatured DNA at low salt concentration, but at high salt concentration RNA polymerase I effectively transcribed denatured DNA. RNA polymerase II more effectively transcribed denatured DNA. In AH-130 cells the activity of RNA polymerase I was 4 to 5 times higher than RNA polymerase II, and in rat liver the activity of RNA polymerase I was 1.5 to 2 times higher than RNA polymerase II. The activity of RNA polymerase I in AH-130 cells may have increased by induction.

Ammonium Sulfate↗