Question 11

(Multiple Choice)

How does RecA bring about strand exchange?


A)RecA acts as a helicase,unwinding DNA in localized regions
B)RecA monomers bind to ssDNA to form a nucleoprotein filament
C)RecA monomers interact only with ssDNA and immediately dissociate when binding to dsDNA
D)RecA forms a tetramer that wraps around DNA at specific sites that must be cleaved by a nuclease
E)none of the above

Answer