FIG. 3.

The cleavage site of Mus81-Mms4 is sequence independent. (A) 3′ flap junctions were incubated in the presence (+) or absence (−) of Mus81-Mms4, and the products were resolved by sequencing gel electrophoresis alongside a chemical sequencing ladder of the labeled oligonucleotide. As indicated, the Maxam-Gilbert ladder of products runs faster than corresponding fragments terminating in a 3′ OH. (B) Sequences, structures, and cleavage sites of the substrates used in the experiment whose results are shown in panel A.