Characterization of the monomeric and complex-associated forms of the gag-onc fusion proteins of three isolates of feline sarcoma virus: phosphorylation, kinase activity, acylation, and kinetics of complex formation.
The gag-onc fusion proteins of three isolates of feline sarcoma virus (ST-FeSV, GA-FeSV, TP1-FeSV) from a stable noncovalent complex with two cellular phosphoproteins, pp90 and pp50. These two phosphoproteins are the same phosphoproteins which have been shown to complex with the transforming proteins of Rous sarcoma virus, Fujinami sarcoma virus, Yamaguchi 73 virus (Lipsich et al., 1982), and PRCII avian sarcoma virus (Adkins et al., 1982). Both the monomeric and complex-associated gag-onc fusion proteins are phosphorylated on serine, threonine, and tyrosine; however, quantitative and/or qualitative differences in phosphorylation of the two species were apparent. Only the monomeric form of the gag-onc proteins was able to undergo tyrosine specific autophosphorylation in an in vitro kinase reaction. Both the monomeric and complex-associated forms of the proteins were acylated, the complex-associated molecules to a greater degree. Pulse-chase experiments indicated that newly synthesized gag-onc molecules become rapidly incorporated into the complex and that a significant amount of these molecules remained associated with the complex for more than 20 hr.
Ziemiecki
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D000215:Acylation; D000818:Animals; D002415:Cats; D002478:Cells, Cultured; D005347:Fibroblasts; D015683:Gene Products, gag; D007700:Kinetics; D010750:Phosphoproteins / Q000378:metabolism*; D010766:Phosphorylation; D010768:Phosphoserine / Q000032:analysis; D010769:Phosphothreonine / Q000032:analysis; D019000:Phosphotyrosine; D011505:Protein-Tyrosine Kinases / Q000378:metabolism; D012190:Retroviridae / Q000032:analysis*; D012191:Retroviridae Proteins / Q000032:analysis / Q000378:metabolism*; D005253:Sarcoma Viruses, Feline / Q000032:analysis*; D014443:Tyrosine / Q000031:analogs & derivatives / Q000032:analysis
D015683:Gene Products, gag; D010750:Phosphoproteins; D012191:Retroviridae Proteins; D010769:Phosphothreonine; D010768:Phosphoserine; D019000:Phosphotyrosine; D014443:Tyrosine; D011505:Protein-Tyrosine Kinases