Referenced in: none

Automatically associated channels: Kir6.2

Title: Intramolecular interaction of SUR2 subtypes for intracellular ADP-Induced differential control of K(ATP) channels.

Authors: Kenji Matsushita, Kengo Kinoshita, Tetsuro Matsuoka, Akikazu Fujita, Takashi Fujikado, Yasuo Tano, Haruki Nakamura, Yoshihisa Kurachi

Journal, date & volume: Circ. Res., 2002 Mar 22 , 90, 554-61

PubMed link: http://www.ncbi.nlm.nih.gov/pubmed/11909819

Abstract
ATP-sensitive K+ (K(ATP)) channels are composed of sulfonylurea receptors (SURs) and inwardly rectifying Kir6.2-channels. The C-terminal 42 amino acid residues (C42) of SURs are responsible for ADP-induced differential activation of K(ATP) channels in SUR-subtypes. By examining ADP-effect on K(ATP) channels containing various chimeras of SUR2A and SUR2B, we identified a segment of 7 residues at central portion of C42 critical for this phenomenon. A 3-D structure model of the region containing the second nucleotide-binding domain (NBD2) of SUR and C42 was developed based on the structure of HisP, a nucleotide-binding protein forming the bacterial Histidine transporter complex. In the model, the polar and charged residues in the critical segment located within a distance that allows their electrostatic interaction with Arg1344 at the Walker-A loop of NBD2. Therefore, the interaction might be involved in the control of ADP-induced differential activation of SUR2-subtype K(ATP) channels.