Data/hora: 04/06/2024 12:08:01

Provedor de dados: | 48
País: | Chile
Título: | Characterization of the long-terminal repeat single-strand tail-binding site of Moloney-MuLV integrase by crosslinking
Autores: | VERA,JORGE; VALENZUELA,BEATRIZ; ROTH,MÓNICA J; LEÓN,ÓSCAR.
Data: | 2008-01-01
Ano: | 2008
Palavras-chave: | Integrase; Retrovirus; Crosslinking.
Resumo: | Processing of viral DNA by retroviral integrase leaves a dinucleotide single-strand overhang in the unprocessed strand. Previous studies have stressed the importance of the 5' single-stranded (ss) tail in the integration process. To characterize the ss-tail binding site on M-MuLV integrase, we carried out crosslinking studies utilizing a disintegration substrate that mimics the covalent intermediate formed during integration. This substrate carried reactive groups at the 5' ss tail. A bromoacetyl derivative with a side chain of 6 A was crosslinked to the mutant IN 106-404, which lacks the N-terminal domain, yielding a crosslinked complex of 50 kDa. Treatment of IN 106-404 with N-ethylmaleimide (NEM) prevented crosslinking, suggesting that Cys209 was involved in the reaction. The reactivity of Cys209 was confirmed by crosslinking of a more specific derivative carrying maleimide groups that spans 8A approximately. In contrast, WT IN was not reactive, suggesting that the N-terminal domain modifies the reactivity of the Cys209 or the positioning of the crosslinker side chain. A similar oligonucleotide-carrying iodouridine at the 5'ss tail reacted with both IN 106-404 and WT IN upon UV irradiation. This reaction was also prevented by NEM, suggesting that the ss-tail positions near a peptide region that includes Cys209
Tipo: | Journal article
Idioma: | Inglês
Identificador: | http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-97602008000100009
Editor: | Sociedad de Biología de Chile
Formato: | text/html
Fonte: | Biological Research  v.41 n.1 2008