recA protein promotes homologous-pairing and strand-exchange reactions between duplex DNA molecules.

AUTOR(ES)

West, S C

RESUMO

Purified recA protein, product of the recA+ gene, promotes homologous pairing between intact covalent circular duplex DNA and circular single-stranded DNA carrying a short hybridized fragment [West, S. C., Cassuto, E. & Howard-Flanders, P. (1981) Nature (London) 290, 29-33.]. In this paper we investigate the interaction of duplex fragments with circular single-stranded DNA carrying the hybridized fragment and find that recA protein promotes an efficient strand-exchange reaction between interacting DNA molecules. The exchange is dependent upon linear duplex DNA fragments that are homologous to, but extend beyond, the short fragment present on the hybridized DNA substrate. The reactions require stoichiometric amounts of recA protein and the presence of ATP.

Documentos Relacionados

• Genetic recombination: recA protein promotes homologous pairing between duplex DNA molecules without strand unwinding.
• Initiation of genetic recombination: homologous pairing between duplex DNA molecules promoted by recA protein.
• Nucleosomes on linear duplex DNA allow homologous pairing but prevent strand exchange promoted by RecA protein.
• Can recA protein promote homologous pairing between duplex regions of DNA?
• Identification of homologous pairing and strand-exchange activity from a human tumor cell line based on Z-DNA affinity chromatography.