Abstract: The present disclosure relates to Cas12 proteins and uses thereof. In certain embodiments, a Cas12 protein is provided whose amino acid sequence has at least 50% sequence identity to SEQ ID NO: 1 and includes one, two, or more amino acid differences relative to SEQ ID NO: 1. In certain embodiments, the Cas12 protein has at least 50% sequence identity to SEQ ID NO: 18. In certain embodiments, the Cas12 protein recognizes a PAM sequence of A. In certain embodiments, gene-editing efficiency of a wild-type Cas12 protein in mammalian cells is improved by introducing rational and irrational amino acid mutations. In certain embodiments, the Cas12 protein exhibits increased editing efficiency and/or a reduced off-target rate and, by virtue of recognizing a single-base A PAM, enables editing of target sequences that were previously difficult to edit, thereby substantially expanding the range of editable targets.

Abstract: Provided are a mutated V-type CRISPR enzyme and use thereof. By means of the protein mutation rational mutagenesis technology, the restriction on the recognition and cleavage of DNA substrates by RuvC in Cas12a or Cas12b is removed, so that RNA substrates can be efficiently recognized and cleaved, and the problem of insufficient RNA substrate recognition efficiency in practical applications is solved. The reaction efficiency of Cas12 with the RNA substrates after the activation of trans-cleavage activity is improved, and the reporting efficiency of Cas12 using an RNA probe is improved.

Abstract: Disclosed is a Cas12 protein, a guide polynucleotide, an inactivated Cas12 mutant, a fusion protein or conjugate including the Cas12 protein, an isolated nucleic acid, a CRISPR-Cas12 system, a vector system, a delivery system, a cell, a pharmaceutical composition, and a kit, and uses thereof.

Abstract: Cas12 protein, guide polynucleotide, inactivated Cas12 mutant, fusion protein or conjugate including the Cas 12 protein, isolated nucleic acid, CRISPR-Cas12 system, vector system, delivery system, cell, pharmaceutical composition, and kit, and the use thereof are provided.

Abstract: Provided is a method for detecting a target nucleic acid in a sample, comprising the following steps: reacting the sample with a mixed reaction system consisting of a sgRNA-Cas system and a recombinase-aid isothermal amplification system; and detecting a detectable signal generated by the reaction after the reaction is completed. The sgRNA-Cas system comprises a Cas12b protein and a sgRNA targeting the target nucleic acid; the recombinase-aid isothermal amplification system comprises a primer, a single-stranded DNA reporter molecule that generates the detectable signal after being cleaved. When a reagent user operates, a sample adding and mixing operation of stopping the reaction midway to add reaction component of the second step is leaved out, so that uniformity and coherence of the operation are better, facilitating the improvement of reaction precision. The operation of opening a reaction tube after the amplification reaction of recombinant polymerase is omitted.