-
公开(公告)号:US20220162620A1
公开(公告)日:2022-05-26
申请号:US17053713
申请日:2019-05-06
Applicant: Massachusetts Institute of Technology
Inventor: Pranam Chatterjee , Noah Michael Jakimo , Joseph M Jacobson
Abstract: Applications of a Streptococcus Cas9 ortholog from Streptococcus macacae (Smac Cas9), possessing minimal adenine-rich PAM specificity, include an isolated Streptococcus macacae Cas9 protein or transgene expression thereof, a CRISPR-associated DNA endonuclease with PAM interacting domain amino acid sequences that are at least 80% identical to that of the isolated Streptococcus macacae Cas9 protein, and an isolated, engineered Streptococcus pyogenes Cas9 (Spy Cas9) protein with a PID as either the PID amino acid composition of the isolated Streptococcus macacae Cas9 (Smac Cas9) protein or of a CRISPR-associated DNA endonuclease with PID amino acid sequences that are at least 80% identical to that of the isolated Streptococcus macacae Cas9 protein. A method for altering expression of at least one gene product employs Streptococcus macacae Cas9 endonucleases in complex with guide RNA, for specific recognition and activity on a DNA target immediately upstream of either an “NAA” or “NA” or “NAAN” PAM sequence.