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Biomedical subjects

R F Weaver

Publications and source records attributed to R F Weaver.

41 records · Page 3Linked to original sources
PubMed1971

Molecular structures of DNA-dependent RNA polymerases (II) from calf thymus and rat liver.

DNA-dependent RNA polymerase II has been purified to high specific activity and apparent homogeneity from both calf thymus and rat liver. Two form II enzymes are present in rat-liver preparations, one with the molecular structure [(190,000)(1)(150,000)(1)(35,000)(1)(25,000)(1)], the other with a molecular structure of [(170,000)(1)(150,000)(1)(35,000)(1)(25,000)(1)] (molecular weights are within +/-5% but the absolute values are approximate). Inclusion of a proteolytic inhibitor during the isolation procedure decreases the proportion of the molecule containing the 170,000 subunit. Calf-thymus RNA polymerase preparations typically exhibit four components on polyacrylamide gels that contain sodium dodecyl sulfate, with an apparent molecular structure of [(190,000)(1)(150,000)(1)(35,000)(1)(25,000)(1)]. In addition, some calf-thymus polymerase II preparations contain small quantities of the [(170,000)(1)(150,000)(1)(35,000)(1)(25,000)(1)] species; the quantity of this species may also be increased from less than 5% in the normal preparation to at least 40% in an "aged" preparation. Thus, the 170,000 subunit may be derived from the 190,000 subunit in both tissues. Until unequivocal evidence is obtained on this point, however, the possibility that the large subunits are unique species should not be eliminated. The general structural similarity of the eukaryotic RNA polymerase II with that of the prokaryotic polymerase suggests that the modes of action and regulation may be analogous.

Acrylamides↗
PubMed1970

Isolation of -L-glutaminyl 4-hydroxybenzene and -L-glutaminyl 3,4-benzoquinone: a natural sulfhydryl reagent, from sporulating gill tissue of the mushroom Agaricus bisporus.

Early in the development of spores, there appears in gill tissue of the mushroom Agaricus bisporus a red pigment that inhibits mitochondrial respiration. The inhibitor and its immediate precursor were isolated from the mushroom and identified as gamma-L-glutaminyl 3,4-benzoquinone (I) and gamma-L-glutaminyl 4-hydroxybenzene (II), respectively, neither of which had previously been described. II was synthesized chemically and the synthetic material was identical with isolated II in all regards. An enzyme that oxidizes II to I was isolated concurrently. I reacts unusually rapidly, completely, and at low concentration with the sulfhydryl groups of various mitochondrial enzymes, accounting for its originally observed properties. It may also prove of value as a general inhibitor of sulfhydryl-dependent enzymes.

Basidiomycota↗
PubMedDate not supplied

Sex linkage of minisatellite bands in bobcats (Felis rufus).

Minisatellite DNA profiles using the multilocus human probe 33.6 are presented for 27 captive bobcats (Felis rufus) of documented geographic and genetic origins. The results show that 30% of the finger-printing bands present in males are sex linked. The effect of sex on band sharing was attributed to the presence of male-specific hemizygotic bands belonging to a minisatellite cluster located in the nonrecombinant region of the Y chromosome. A combination of mechanisms might drive the dynamics of minisatellite loci and allow different evolutionary rates depending on the recombinational capability of the chromosomal locations involved. We discuss the utility of sex-linked fingerprinting bands as genetic markers for the study and management of bobcats.

Animals↗