Bj. Rao et Cm. Radding, FORMATION OF BASE TRIPLETS BY NON-WATSON-CRICK BONDS MEDIATES HOMOLOGOUS RECOGNITION IN RECA RECOMBINATION FILAMENTS, Proceedings of the National Academy of Sciences of the United Statesof America, 91(13), 1994, pp. 6161-6165
Whereas complementary strands of DNA recognize one another by forming
Watson-Crick base pairs, the way in which RecA protein enables a singl
e strand to recognize homology in duplex DNA has remained unknown. Rec
ent experiments, however, have shown that a single plus strand in the
RecA filament can recognize an identical plus strand via bonds that, b
y definition, are non-Watson-Crick, In experiments reported here, base
substitutions had the same qualitative and quantitative effects on th
e pairing of two identical strands in the RecA filament as on the reco
gnition of duplex DNA by a third strand, indicating that similar non-W
atson-Crick interactions govern both reactions.