Enhanced Taq Variant Enables Efficient Genome Editing Testing and Mutation Detection.

Publisher: Mary Ann Liebert, Inc Country of Publication: United States NLM ID: 101738191 Publication Model: Print-Electronic Cited Medium: Internet ISSN: 2573-1602 (Electronic) Linking ISSN: 25731599 NLM ISO Abbreviation: CRISPR J Subsets: MEDLINE

Original Publication: [New Rochelle, NY] : Mary Ann Liebert, Inc., [2018]-

CRISPR-Cas Systems*/genetics ; Gene Editing*; Alleles ; Mutation ; Taq Polymerase/metabolism

Detection of genome editing with quantitative polymerase chain reaction (PCR) primarily relies on and is limited by its ability to discriminate genome modification from the wild-type sequence. An enhanced DNA polymerase variant with superior specificity is needed for this application. Here, we perform semi-rational molecular evolution on full-length Taq polymerase to screen high-specific variants that meet the requirements of gene variation detection. We substituted each of the 40 polar amino acids in direct contact with the primer/template duplex and conducted extensive random mutagenesis to generate a Taq mutation library. Screening on a quantitative PCR system with insertion and deletion-containing templates identified a series of improved Taq variants. We demonstrate that the Taq388 variant bearing three amino acid substitutions, S577A, W645R, and I707V, has improved sensitivity to insertion and deletion-derived primer/template mismatch by a ΔCt value of 25-26 and is superior for application in evaluating CRISPR-Cas9 editing efficiency and single-cell clone genotyping. In addition, the Taq variant shows substantial potential for single-nucleotide polymorphism detection by means of allele-specific PCR because of its high sensitivity to mismatches.

EC 2.7.7.- (Taq Polymerase)

Date Created: 20220125 Date Completed: 20220404 Latest Revision: 20220405

20240105

10.1089/crispr.2021.0105

35076264