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921.
922.
Abraham Grossman 《Biochemical genetics》1980,18(7-8):765-780
When Adh
F
/Adh
S
heterozygote homogenates are stained after electrophoresis, considerable variation is observed in the activity ratio of the FF dimer to the SS dimer. Two Adh
S
strains showed a sharp, consistent difference when crossed to a common Adh
F
strain. Optical scanning and genetic analysis confirmed that this difference originates close to the Adh locus. Since the morphs varied concordantly in their activities on numerous alcohols, and since aging and heat-treatment experiments failed to reveal a stability difference, it is proposed that the difference is regulatory in nature, affecting ADH synthesis and primarily cis-acting. A survey of wild flies revealed additional variation in the FF/SS activity ratio. Further genetic analysis showed that the basis of this variation is not restricted to the second chromosome. Furthermore, modification of the activity ratio implies some degree of allelespecificity on the part of the modifiers.This work was supported in part by money collected by Jewish Community of Iowa City, Iowa, and by NSF Grant 76-01903 to Roger Milkman. 相似文献
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924.
《Neuron》2022,110(17):2815-2835.e13
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927.
The structural polypeptides of 12 baculovirus isolates which included nuclear polyhedrosis viruses (NPVs) and granulosis viruses (GVs) obtained from four different species of the insect genus Heliothis collected in different geographical regions of the world were characterized using sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The matrix proteins were compared according to their molecular weights and peptide profiles produced after limited proteolysis. Examination of the matrix and virion polypeptide profiles revealed three major polypeptide phenotypes which corresponded to the three baculovirus morphological groups; singly embedded nuclear polyhedrosis viruses (SNPVs), multiply embedded nuclear polyhedrosis viruses (MNPVs), and granulosis viruses (GVs). Enveloped nucleocapsid polypeptide profiles of isolates within each NPV phenotype differed in only one polypeptide whereas the two GV isolates differed by as many as five polypeptides. Nucleocapsid polypeptide profiles of isolates within each of the NPV subgroups were identical while those profiles from the GV nucleocapsids differed slightly in molecular weight of one polypeptide. 相似文献
928.
A 'null' activity variant for the major liver isozyme of aldehyde oxidase (AOX-1) in adult male mice and an electrophoretically distinct, high activity variant of the second liver isozyme (AOX-2) were used to examine the segregation of the genetic loci encoding these enzymes (Aox-1 and Aox-2 respectively) in breeding studies. A single recombinant between these loci was observed among the 147 backcross progeny examined, which confirms a previous report (Holmes, 1979) for close linkage and genetic distinctness of the two loci. An activity variant for mouse liver xanthine oxidase (XOX) is also reported which behaved as though controlled by codominant alleles at a single locus (designated Xox-1 ). Genetic analyses showed that the Xox-1 locus segregated independently of the multiple- A ox loci. 相似文献
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