4L6U

Crystal structure of AF1868: Cmr1 subunit of the Cmr RNA silencing complex

Summary for 4L6U

• Entry DOI: 10.2210/pdb4l6u/pdb
• Descriptor: Putative uncharacterized protein (2 entities in total)
• Functional Keywords: ferredoxin, unknown function
• Biological source: Archaeoglobus fulgidus
• Total number of polymer chains: 2
• Total formula weight: 76033.94

Authors

Sun, J.,Jeon, J.H.,Shin, M.,Shin, H.C.,Oh, B.H.,Kim, J.S. (deposition date: 2013-06-12, release date: 2014-02-12, Last modification date: 2024-03-20)

Primary citation

Sun, J.,Jeon, J.H.,Shin, M.,Shin, H.C.,Oh, B.H.,Kim, J.S.
Crystal structure and CRISPR RNA-binding site of the Cmr1 subunit of the Cmr interference complex
Acta Crystallogr.,Sect.D, 70:535-543, 2014

PubMed Abstract: A multi-subunit ribonucleoprotein complex termed the Cmr RNA-silencing complex recognizes and destroys viral RNA in the CRISPR-mediated immune defence mechanism in many prokaryotes using an as yet unclear mechanism. In Archaeoglobus fulgidus, this complex consists of six subunits, Cmr1-Cmr6. Here, the crystal structure of Cmr1 from A. fulgidus is reported, revealing that the protein is composed of two tightly associated ferredoxin-like domains. The domain located at the N-terminus is structurally most similar to the N-terminal ferredoxin-like domain of the CRISPR RNA-processing enzyme Cas6 from Pyrococcus furiosus. An ensuing mutational analysis identified a highly conserved basic surface patch that binds single-stranded nucleic acids specifically, including the mature CRISPR RNA, but in a sequence-independent manner. In addition, this subunit was found to cleave single-stranded RNA. Together, these studies elucidate the structure and the catalytic activity of the Cmr1 subunit.

PubMed: 24531487
DOI: 10.1107/S1399004713030290

Experimental method

X-RAY DIFFRACTION (2.5 Å)