Crystal structure of a novel RNA motif that allows for precise positioning of a single metal ion.

Crystal structure of a novel RNA motif that allows for precise positioning of a single metal ion.
J Inorg Biochem. 2017 Sep 09;176:140-143
Authors: Kanazawa H, Kondo J
Abstract
We have determined a crystal structure of an RNA duplex containing a novel metal-binding motif. The motif is composed of two sheared G○A base pairs, two unpaired A residues and four phosphate groups in close proximity. Four A residues make an A-A-A-A stacking column at the minor groove side and two G bases are highly inclined, thereby forming the pocket-shaped motif at the major groove side. In the present structure, a hydrated Sr(2+) ion exists in the pocket and binds to the O6 and N7 atoms of the two G bases and four phosphate groups. According to the previously-reported metal-binding properties to RNA molecules, many of divalent cations, such as Mg(2+), Mn(2+), Co(2+), Zn(2+), Ba(2+), Pb(2+) and Cd(2+), may bind to the motif. This metal-binding motif can be used as a modular building block that allows for precise positioning of a single metal ion in functional nucleic acid molecules.
PMID: 28898762 [PubMed - as supplied by publisher]

Source: Journal of Inorganic Biochemistry - September 9, 2017 Category: Biochemistry Authors: Kanazawa H, Kondo J Tags: J Inorg Biochem Source Type: research