Zhang Feng's latest science paper: a CRISPR CAS system that can cut proteins
CRISPR Cas system is an ancient immune system widely existing in bacteria and archaea, which is used to resist the invasion of foreign genetic elements (such as bacteriophages). Through their research, scientists have developed a series of powerful gene editing tools such as CRISPR-Cas9. These gene editing tools are RNA guided nucleases that cut DNA or RNA. In addition, there is CRISPR related transposase (CAST) system, which guides Tn7 like genetic elements to specific DNA sequences through CRISPR effectors of nuclease inactivation, so as to achieve RNA guided DNA insertion.
In addition to CAST system, there may be more CRISPR CAS related systems to be discovered and explored. In August 2022, Professor Cute Long/Dr. Hu Chunyi of Cornell University published a paper in Science [1]. This study revealed that CRISPR Cas related system Cas7-11 can target and activate protease Csx29 through gRNA guidance, and protease Csx29 can cleave protein substrate. Cas7-11 and Csx29 can form stable protein complexes, but the substrates and functions of related proteases are still unclear.
On November 3, 2022, Zhang Feng's team published a research paper entitled RNA activated protein cleaning with a CRISPR associated endpoint in Science [2].
This study identified the protein substrate, structure and mechanism of action of Cas7-11, a III-E CRISPR related protease (CASP), revealed the new function of CRISPR system beyond nuclease, and developed RNA sensing that can be used to detect RNA in vitro and human cells.