Figure 3. Sequence analysis of strand transfer reaction products.

a-d, Sequence logos representing nucleotide frequencies at PFV integration sites in vitro using wild type (a), R329S (b), R329E (c), or A188S (d) INs. Target DNA sequences as joined to the viral DNA ends were used in the alignments. Arrowheads indicate sites of strand transfer, and dotted lines symmetry axes of the integration site consensi; the strict two-fold symmetry is imposed by the use of intasomes containing pairs of U5 viral DNA ends.