4c40

Publication Abstract from PubMed

L7Ae is a member of a protein family that binds kink-turns (k-turns) in many functional RNA species. We have solved the X-ray crystal structure of the near-consensus sequence Kt-7 of Haloarcula marismortui bound by Archaeoglobus fulgidus L7Ae at 2.3-A resolution. We also present a structure of Kt-7 in the absence of bound protein at 2.2-A resolution. As a result, we can describe a general mode of recognition of k-turn structure by the L7Ae family proteins. The protein makes interactions in the widened major groove on the outer face of the k-turn. Two regions of the protein are involved. One is an alpha-helix that enters the major groove of the NC helix, making both nonspecific backbone interactions and specific interactions with the guanine nucleobases of the conserved G*A pairs. A hydrophobic loop makes close contact with the L1 and L2 bases, and a glutamate side chain hydrogen bonds with L1. Taken together, these interactions are highly selective for the structure of the k-turn and suggest how conformational selection of the folded k-turn occurs.

The molecular recognition of kink-turn structure by the L7Ae class of proteins.,Huang L, Lilley DM RNA. 2013 Oct 22. PMID:24149842^[1]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.