tailieunhanh - Báo cáo khoa học: Structure of the atrial natriuretic peptide receptor extracellular domain in the unbound and hormone-bound states by single-particle electron microscopy

Atrial natriuretic peptide (ANP) plays a major role in blood pressure and volume regulation. ANP activities are mediated by a cell surface, single-span transmembrane receptor linked to its intrinsic guanylate cyclase activ-ity. The crystal structures of the dimerized ANP receptor extracellular domain (ECD) with and without ANP have revealed a novel hormone- | ỊFEBS Journal Structure of the atrial natriuretic peptide receptor extracellular domain in the unbound and hormone-bound states by single-particle electron microscopy Haruo Ogawa1 Yue Qiu1 Liming Huang2 Suk-Wah Tam-Chang2 Howard S. Young3 and Kunio S. Misono1 1 Department of Biochemistry University of Nevada Reno NV USA 2 Department of Chemistry University of Nevada Reno NV USA 3 Department of Biochemistry University of Alberta Edmonton Canada Keywords fluorescence spectroscopy natriuretic peptide receptor single particle reconstruction transmembrane signal transduction Correspondence H. S. Young Department of Biochemistry University of Alberta Edmonton AB T6G 2H7 Canada Fax 1 780 492 0095 Tel 1 780 492 3931 E-mail hyoung@ K. S. Misono Department of Biochemistry University of Nevada Schoolof Medicine Reno NV 89557 USA Fax 1 775 784 1419 Tel 1 775 784 4690 E-mail kmisono@ Received 10 October 2008 revised 14 December 2008 accepted 22 December 2008 doi Atrial natriuretic peptide ANP plays a major role in blood pressure and volume regulation. ANP activities are mediated by a cell surface singlespan transmembrane receptor linked to its intrinsic guanylate cyclase activity. The crystal structures of the dimerized ANP receptor extracellular domain ECD with and without ANP have revealed a novel hormone-induced rotation mechanism occurring in the juxtamembrane region that appears to mediate signal transduction Ogawa H Qiu Y Ogata CM Misono KS 2004 J Biol Chem 279 28625-28631 . However the ECD crystal packing contains two major intermolecular contacts that suggest two possible dimer pairs head-to-head hh and tail-to-tail tt dimers associated via the membrane-distal and membrane-proximal subdomains respectively. The existence of these two potential dimer forms challenges the proposed signaling mechanism. In this study we performed single-particle electron microscopy EM to determine the ECD dimer structures occurring in the .