title: Mutations in HIV-1 reverse transcriptase cause misfolding and miscleavage by the viral protease.
abstract: Previous work on mutations in the thumb of HIV-1 reverse transcriptase (RT) showed that the majority of the mutant RTs were degraded (by the viral protease) to various extents in virions. This degradation was, in most cases, temperature sensitive, and presumably was due to a partial unfolding of the protein at 37°C. We used recombinant proteins to investigate the effects of the mutations on the thermal stability and proteolytic degradation of RT. Both subunits contribute to the stability of RT. In general, the differences in stability between the mutants and WT were greater if the mutation was in p51 rather than p66. Expressing the Pol polyprotein containing the RT mutants in Escherichia coli produced results similar to what was seen in virions; the mutant RTs were misfolded and/or degraded at 37°C, but were better folded and processed at 30°C.
authors.affiliation: HIV Drug Resistance Program, Center for Cancer Research, National Cancer Institute, National Institutes of Health, PO Box B, Frederick, MD 21702, USA. dunnli@mail.nih.gov
authors.forename: Linda L
authors.initials: LL
authors.lastname: Dunn
authors.forename: Paul L
authors.initials: PL
authors.lastname: Boyer
authors.forename: Patrick K
authors.initials: PK
authors.lastname: Clark
authors.forename: Stephen H
authors.initials: SH
authors.lastname: Hughes
mesh_terms: D004795:Enzyme Stability; D004926:Escherichia coli / Q000235:genetics; D016333:HIV Protease / Q000378:metabolism*; D054303:HIV Reverse Transcriptase / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D015497:HIV-1 / Q000201:enzymology* / Q000235:genetics; D050505:Mutant Proteins / Q000235:genetics / Q000378:metabolism; D017510:Protein Folding; D055550:Protein Stability; D059748:Proteolysis; D011994:Recombinant Proteins / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism; D013696:Temperature
chemical_list: D050505:Mutant Proteins; D011994:Recombinant Proteins; C514824:reverse transcriptase, Human immunodeficiency virus 1; D054303:HIV Reverse Transcriptase; D016333:HIV Protease
keywords: Differential scanning fluorescence; HIV-1; Protease; Reverse transcriptase; Stability