V-type CRISPR / Cas effector protein for cleavage of ssDNA and detection of target DNA

摘要

Compositions and methods for detecting target DNA (double or single strand) in a sample are provided. In some embodiments, the method uses (a) samples as (i) V-type CRISPR / Cas effector proteins (eg, Cas12 proteins such as Cas12a, Cas12b, Cas12c, Cas12d, Cas12e), (ii) guide RNAs. (Contains a region that binds to the V-type CRISPR / Cas effector protein and a guide sequence that hybridizes with the target DNA), and (iii) is single-stranded (ie, "single-stranded detection DNA") and guide. Contacting with a detection DNA that does not hybridize with the guide sequence of the RNA, and (b) measuring the detectable signal produced by cleavage of the single-stranded detection DNA (by the V-type CRISPR / Cas effector protein). ,including. Also provided are compositions and methods for cleaving single-strand DNA (eg, non-target ssDNA) inside cells, for example. [Selection diagram] FIG. 3A