3UR3

Structure of the Cmr2 subunit of the CRISPR RNA silencing complex

Summary for 3UR3

• Entry DOI: 10.2210/pdb3ur3/pdb
• Related: 3UNG
• Descriptor: Cmr2dHD, CALCIUM ION, ZINC ION, ... (4 entities in total)
• Functional Keywords: ferredoxin fold, nucleotide-binding, polymerase, cmr complex, unknown function
• Biological source: Pyrococcus furiosus
• Cellular location: Cytoplasm : Q8U1S6
• Total number of polymer chains: 1
• Total formula weight: 80291.97

Authors

Cocozaki, A.I.,Ramia, N.F.,Shao, Y.,Hale, C.R.,Terns, R.M.,Terns, M.P.,Li, H. (deposition date: 2011-11-21, release date: 2012-03-21, Last modification date: 2024-02-28)

Primary citation

Cocozaki, A.I.,Ramia, N.F.,Shao, Y.,Hale, C.R.,Terns, R.M.,Terns, M.P.,Li, H.
Structure of the Cmr2 Subunit of the CRISPR-Cas RNA Silencing Complex.
Structure, 20:545-553, 2012

PubMed Abstract: Cmr2 is the largest and an essential subunit of a CRISPR RNA-Cas protein complex (the Cmr complex) that cleaves foreign RNA to protect prokaryotes from invading genetic elements. Cmr2 is thought to be the catalytic subunit of the effector complex because of its N-terminal HD nuclease domain. Here, however, we report that the HD domain of Cmr2 is not required for cleavage by the complex in vitro. The 2.3Å crystal structure of Pyrococcus furiosus Cmr2 (lacking the HD domain) reveals two adenylyl cyclase-like and two α-helical domains. The adenylyl cyclase-like domains are arranged as in homodimeric adenylyl cyclases and bind ADP and divalent metals. However, mutagenesis studies show that the metal- and ADP-coordinating residues of Cmr2 are also not critical for cleavage by the complex. Our findings suggest that another component provides the catalytic function and that the essential role by Cmr2 does not require the identified ADP- or metal-binding or HD domains in vitro.

PubMed: 22405013
DOI: 10.1016/j.str.2012.01.018

Experimental method

X-RAY DIFFRACTION (2.405 Å)