Homologous recombination

Homologous recombination is one of the most fundamental biomolecular processes involving DNA.  It plays a key role in the evolution of organisms from bacteria to man, generating genetic diversity by reshuffling genes in eukaryotes, and by enabling the import of new ones in prokaryotes.

Furthermore, it constitutes one of the main pathways for the repair of DNA lesions. During homologous recombination, single-stranded DNA exchanges one of the strands in a DNA duplex, provided enough sequence homology exists between the two, as illustrated:

This process is catalyzed by enzymes called recombinases, such as RecA in bacteria and Rad51 in eukaryotes.  We attempt to dissect the  elementary steps and mechanisms through which recombination proceeds from a Statistical Mechanics and Molecular Biology viewpoint and its fidelity when the participating sequences are not fully homologous.  We seek to elucidate how the search for homology within a huge DNA background takes place, both in vitro using flourescence techniques in ensmble and single-pair modalities, and in vivo.