AUTHOR=Gu Do-Heon , Ha Sung Chul , Kim Jeong-Sun TITLE=A CRISPR RNA Is Closely Related With the Size of the Cascade Nucleoprotein Complex JOURNAL=Frontiers in Microbiology VOLUME=10 YEAR=2019 URL=https://www.frontiersin.org/journals/microbiology/articles/10.3389/fmicb.2019.02458 DOI=10.3389/fmicb.2019.02458 ISSN=1664-302X ABSTRACT=
The currently known prokaryotic adaptive immune system against mobile genetic elements is based on clustered regularly interspaced short palindromic repeats (CRISPR). CRISPR-associated (Cas) proteins and the transcribed short CRISPR RNA (crRNA) molecule form a heterologous ribonucleoprotein complex that neutralizes invading foreign nucleic acids, wherein the crRNA molecule base-pairs with the exogenous genetic elements. In the ribonucleoprotein complexes of the type I CRISPR system, a helical backbone of six identical subunits is commonly found. However, it is not clear how this ribonucleoprotein complex is assembled and what is the determinant factor for its size. We elucidated the crystal structure of the Csy3 subunit of the type I-F ribonucleoprotein complex from