Fig. 3.

Cas3″ is the effector nuclease of type I-A crRNP. a SDS- PAGE showing recombinant wild-type (wt.) Cas3″ and HD-AA mutant (mut.) Cas3″ proteins. Molecular weight marker proteins (sizes in kDa) are labeled (M). b DNA cleavage with Csa crRNP [+, assembled with crRNA, Csa4–1, Cas3′, Cas5a, Csa2, Csa5 and either Cas3″ (wild-type (wt.) or HD-AA mutant (mut.)]. 5′ radiolabeled (³²P) DNA size-standard (Affymetrix, 10–100 bases) is labeled (M). c Gel mobility shift assay of corresponding samples in b. DNA bound by Csa crRNP (black triangle) and free DNA is indicated. b and c Reactions in the absence of any Csa protein are labeled (−) and the upper label indicates location of 5′ radiolabel (³²P) in either the nontarget or target strand of double-stranded DNA