RECOMBINANT HIV-1 NUCLEOCAPSID PROTEIN ACCELERATES HIV-1 REVERSE-TRANSCRIPTASE CATALYZED DNA STRAND TRANSFER-REACTIONS AND MODULATES RNASE-H ACTIVITY

The effect of recombinant nucleocapsid protein (NCp7) from human immun odeficiency virus type 1 (HIV-1) on HIV-1 reverse transcriptase (HIV-1 RT) catalyzed DNA strand transfer reactions has been studied using ki netic methods with a defined template-primer model system. NCp7 is sho wn to modulate both the rate and the efficiency of DNA strand transfer synthesis. Evidence is presented that supports the role of NCp7 in ca talyzing the annealing of a nascent DNA intermediate and RNA acceptor template during strand transfer. NCp7 was also found to enhance the ri bonuclease H activity of HIV-1 RT and change the specificity of RNA hy drolysis, suggesting a direct role of NCp7 in HIV-1 RT catalyzed stran d transfer. The implications of these findings for retroviral reverse transcription are addressed.