Unknown

Dataset Information

0

Spatial domain organization in the HIV-1 reverse transcriptase p66 homodimer precursor probed by double electron-electron resonance EPR.


ABSTRACT: HIV type I (HIV-1) reverse transcriptase (RT) catalyzes the conversion of viral RNA into DNA, initiating the chain of events leading to integration of proviral DNA into the host genome. RT is expressed as a single polypeptide chain within the Gag-Pol polyprotein, and either prior to or following excision by HIV-1 protease forms a 66 kDa chain (p66) homodimer precursor. Further proteolytic attack by HIV-1 protease cleaves the ribonuclease H (RNase H) domain of a single subunit to yield the mature p66/p51 heterodimer. Here, we probe the spatial domain organization within the p66 homodimer using pulsed Q-band double electron-electron resonance (DEER) EPR spectroscopy to measure a large number of intra- and intersubunit distances between spin labels attached to surface-engineered cysteines. The DEER-derived distances are fully consistent with the structural subunit asymmetry found in the mature p66/p51 heterodimer in which catalytic activity resides in the p66 subunit, while the p51 subunit purely serves as a structural scaffold. Furthermore, the p66 homodimer precursor undergoes a conformational change involving the thumb, palm, and finger domains in one of the subunits (corresponding to the p66 subunit in the mature p66/p51 heterodimer) from a closed to a partially open state upon addition of a nonnucleoside inhibitor. The relative orientation of the domains was modeled by simulated annealing driven by the DEER-derived distances. Finally, the RNase H domain that is cleaved to generate p51 in the mature p66/p51 heterodimer is present in 2 major conformers. One conformer is fully solvent accessible thereby accounting for the observation that only a single subunit of the p66 homodimer precursor is susceptible to HIV-1 protease.

SUBMITTER: Schmidt T 

PROVIDER: S-EPMC6731638 | biostudies-literature | 2019 Sep

REPOSITORIES: biostudies-literature

altmetric image

Publications

Spatial domain organization in the HIV-1 reverse transcriptase p66 homodimer precursor probed by double electron-electron resonance EPR.

Schmidt Thomas T   Schwieters Charles D CD   Clore G Marius GM  

Proceedings of the National Academy of Sciences of the United States of America 20190805 36


HIV type I (HIV-1) reverse transcriptase (RT) catalyzes the conversion of viral RNA into DNA, initiating the chain of events leading to integration of proviral DNA into the host genome. RT is expressed as a single polypeptide chain within the Gag-Pol polyprotein, and either prior to or following excision by HIV-1 protease forms a 66 kDa chain (p66) homodimer precursor. Further proteolytic attack by HIV-1 protease cleaves the ribonuclease H (RNase H) domain of a single subunit to yield the mature  ...[more]

Similar Datasets

| S-EPMC7678880 | biostudies-literature
| S-EPMC4441793 | biostudies-literature
| S-EPMC6034511 | biostudies-literature
| S-EPMC8179457 | biostudies-literature
| S-EPMC7765405 | biostudies-literature
| S-EPMC4005681 | biostudies-literature
| S-EPMC10988587 | biostudies-literature
| S-EPMC4412742 | biostudies-literature
2018-12-12 | E-MTAB-7087 | biostudies-arrayexpress
| S-EPMC3057626 | biostudies-literature