PRIMER TRANSFER RNATRP ENHANCES THE INHIBITION OF AVIAN-MYELOBLASTOSIS VIRUS REVERSE-TRANSCRIPTASE BY PYRIDOXAL-5'-PHOSPHATE

In the presence of tRNATrp the inhibition of avian myeloblastosis virus reverse transcriptase by pyridoxal-5′-phosphate is greatly enhanced. This effect of tRNA is specific. While tRNAbeefTrp (the primer of the in vitro DNA synthesis with 35 S viral RNA as template) gives the maximal effect, tRNAbeefVal will not affect the enzyme activity. In the presence of tRNAbeefTrp two additional lysines are titrated with pyridoxal-5′-phosphate as measured by reduction of the enzyme-pyridoxal-5′-phosphate complex with tritiated NaBH4. The effect of tRNA is dependent on the presence of the β subunit of avian myeloblastosis virus reverse transcriptase, since the enzymatic activity of the α subunit, although inhibited by pyridoxal-5′-phosphate, is not affected by tRNA. © 1979.