Characterization of human immunodeficiency virus type 1 Pr160 gag-pol mutants with truncations downstream of the protease domain.
We have constructed a series of HIV-1 Gag-pol mutants by progressive deletion of the pol sequence downstream of the viral protease (PR) domain. Effects of the truncation mutations on virus particle production and Gag particle processing were analyzed. Analysis indicated that removal of the integrase (IN) domain had no major effect on the efficiency of particle processing, but resulted in a marked reduction in virus particle budding. Deletion of both the IN and RNase H domains, however, restored the production of virus particles to wild-type level. The proteolytic processing of virus particle was significantly impaired when the p51RT domain was truncated. All of the truncated Gag-pol proteins could be incorporated into virus particles and demonstrated an immunofluorescence staining pattern similar to that of the wild type (wt). Our data are consistent with the proposal that signals for directing the Gag-pol transport and particle incorporation are determined by its N-terminal Gag domain. Truncated Gag-pol retaining an intact p51RT was able to complement a PR-defective mutant to produce infectious pseudotyped virions, with a virus titer 20-70% of that of wt. Pseudotyped virions produced by the Gag-pol lacking an intact p51RT were noninfectious or poorly infectious. This suggests that an intact p51RT domain is required for the Gag-pol to mediate production of mature infectious virus particles in trans.
Institute of Clinical Medicine, National Yang-Ming University School of Medicine, and Department of Medical Research and Education, Taipei Veterans General Hospital, 201 Sec. 2 Shih-Pai Road, Taipei 11217, Taiwan.
Wei-Hao
WH
Liao
Chin-Tien
CT
Wang
D002460:Cell Line; D015967:Gene Expression Regulation, Viral; D015683:Gene Products, gag / Q000235:genetics* / Q000378:metabolism; D016333:HIV Protease / Q000235:genetics*; D054303:HIV Reverse Transcriptase / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D015497:HIV-1 / Q000235:genetics / Q000378:metabolism* / Q000472:pathogenicity; D006801:Humans; D009154:Mutation; D011498:Protein Precursors / Q000235:genetics* / Q000378:metabolism; D014162:Transfection; D014771:Virion / Q000235:genetics / Q000378:metabolism* / Q000472:pathogenicity; D019065:Virus Assembly; D054301:gag Gene Products, Human Immunodeficiency Virus; D054302:pol Gene Products, Human Immunodeficiency Virus
D015683:Gene Products, gag; D011498:Protein Precursors; D054301:gag Gene Products, Human Immunodeficiency Virus; D054302:pol Gene Products, Human Immunodeficiency Virus; C091950:pr160 gag-pol precursor protein, Human immunodeficiency virus 1; D054303:HIV Reverse Transcriptase; D016333:HIV Protease