Studies on reverse transcriptase of RNA tumor viruses. I. Localization of thermolabile DNA polymerase and RNase H activities on one polypeptide.
AUTOR(ES)
Verma, I M
RESUMO
Purified reverse transcriptase from avian myeloblastosis virus or Rous sarcoma virus consists of two subunits of average mol wt of 100,000 and 60,000. The lower-molecular-weight subunit, alpha, has been isolated from avian myeloblastosis virus, Rous sarcoma virus and a temperature-sensitive mutant of Rous sarcoma virus, LA337. Subunit alpha manifests both the DNA polymerase and RNase H activities associated with purified reverse transcriptase of avian RNA tumor viruses. The thermal inactivation of these enzymatic activities of alpha subunit from the wild-type virus. The results show that both DNA polymerase and RNase H activities associated with the alpha subunit of LA337 are five to seven times more thermolabile then the corresponding alpha subunit from the wild-type virus. It is concluded that (i) both the polymerase and nuclease activities reside on the same polypeptide chain, and (ii) at least the lower-molecular-weight subunit alpha is coded for by the viral RNA.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=354425Documentos Relacionados
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