PMID: 17704815 , Related PDB id: 2YT4

Authors:

Sohn SY, Bae WJ, Kim JJ, Yeom KH, Kim VN, Cho Y

Title:

Crystal structure of human DGCR8 core.

Journal:

Nat Struct Mol Biol. 2007 Sep;14(9):847-53. Epub 2007 Aug 19.

Abstract:

A complex of Drosha with DGCR8 (or its homolog Pasha) cleaves primary microRNA (pri-miRNA) substrates into precursor miRNA and initiates the microRNA maturation process. Drosha provides the catalytic site for this cleavage, whereas DGCR8 or Pasha provides a frame for anchoring substrate pri-miRNAs. To clarify the molecular basis underlying recognition of pri-miRNA by DGCR8 and Pasha, we determined the crystal structure of the human DGCR8 core (DGCR8S, residues 493-720). In the structure, the two double-stranded RNA-binding domains (dsRBDs) are arranged with pseudo two-fold symmetry and are tightly packed against the C-terminal helix. The H2 helix in each dsRBD is important for recognition of pri-miRNA substrates. This structure, together with fluorescent resonance energy transfer and mutational analyses, suggests that the DGCR8 core recognizes pri-miRNA in two possible orientations. We propose a model for DGCR8's recognition of pri-miRNA.