Type |
Article |
Date |
2010-06 |
Language |
English |
Author(s) |
Carayon Kevin1, Leh Herve1, Henry Etienne1, Simon Francoise1, Mouscadet Jean-Francois1, Deprez Eric1 |
Affiliation(s) |
1 : Ecole Normale Super, LBPA, CNRS, F-94235 Cachan, France. |
Source |
Nucleic Acids Research (0305-1048) (Oxford Univ Press), 2010-06 , Vol. 38 , N. 11 , P. 3692-3708 |
DOI |
10.1093/nar/gkq087 |
WOS© Times Cited |
22 |
Abstract |
HIV-1 integrase catalyzes the insertion of the viral genome into chromosomal DNA. We characterized the structural determinants of the 3'-processing reaction specificity-the first reaction of the integration process-at the DNA-binding level. We found that the integrase N-terminal domain, containing a pseudo zinc-finger motif, plays a key role, at least indirectly, in the formation of specific integrase-DNA contacts. This motif mediates a cooperative DNA binding of integrase that occurs only with the cognate/viral DNA sequence and the physiologically relevant Mg(2+) cofactor. The DNA-binding was essentially non-cooperative with Mn(2+) or using non-specific/random sequences, regardless of the metallic cofactor. 2,2'-Dithiobisbenzamide-1 induced zinc ejection from integrase by covalently targeting the zinc-finger motif, and significantly decreased the Hill coefficient of the Mg(2+)-mediated integrase-DNA interaction, without affecting the overall affinity. Concomitantly, 2,2'-dithiobisbenzamide-1 severely impaired 3'-processing (IC(50) = 11-15 nM), suggesting that zinc ejection primarily perturbs the nature of the active integrase oligomer. A less specific and weaker catalytic effect of 2,2'-dithiobisbenzamide-1 is mediated by Cys 56 in the catalytic core and, notably, accounts for the weaker inhibition of the non-cooperative Mn(2+)-dependent 3'-processing. Our data show that the cooperative DNA-binding mode is strongly related to the sequence-specific DNA-binding, and depends on the simultaneous presence of the Mg(2+) cofactor and the zinc effector. |
Full Text |
File |
Pages |
Size |
Access |
30183.pdf |
17 |
958 KB |
Open access |
|