Structural insight into hormone recognition and transmembrane signaling by the atrial natriuretic peptide receptor

Abstract

<jats:p>Atrial natriuretic peptide (ANP) is an endogenous and potent hypotensive hormone that elicits natriuretic, diuretic, vasorelaxant, and anti-proliferative effects, which play a central role in the regulation of blood pressure and volume. To investigate the hormone-binding and membrane signaling mechanisms mediated by the ANP receptor, we elucidated the crystal structures of the ANP receptor extracellular hormone-binding domain (ANPR) complexed with full-length ANP, truncated mutants of ANP, and dendroaspis natriuretic peptide (DNP) isolated from the venom of the green Mamba snake, Dendroaspis angusticeps. The bound peptides possessed pseudo two-fold symmetry to which the tight coupling of the peptide to the receptor and guanylyl cyclase activity was attributed. The crystal structures and our results from kinetic experiments provide insight into the ligand recognition and transmembrane signaling mechanism of the ANP receptor. Our findings provide useful information that can be applied to drug discovery for heart failure therapies.</jats:p>

Purification, characterization, and preliminary serial crystallography diffraction advances structure determination of full-length human particulate guanylyl cyclase A receptor

“…Currently, there is available only the rat pGC-A extracellular domain structure with and without ligand ANP information 22 – 24 . To maximize the functional protein expression in Sf9 insect cells, we replaced the original N-terminal signal peptide with a cleavable signal peptide from influenza hemagglutinin 45 .…”

“…The current structural knowledge of pGC-A was made possible by earlier studies such as the milestone advance of Pandey and Kanungo (1993) 21 , who purified the mouse ECD and demonstrated its binding to ANP. Currently, the structure of only the extracellular domain (residues 1–435, out of 1057) of rat pGC-A is solved 22 – 24 . The relevant Protein Data Bank accession codes are 1DP4 22 for apo rat pGC-A ECD; and 1T34 23 and 7BRG-7BRJ 24 for rat pGC-A ECD with various natriuretic peptide ligands.…”

“…Currently, the structure of only the extracellular domain (residues 1–435, out of 1057) of rat pGC-A is solved 22 – 24 . The relevant Protein Data Bank accession codes are 1DP4 22 for apo rat pGC-A ECD; and 1T34 23 and 7BRG-7BRJ 24 for rat pGC-A ECD with various natriuretic peptide ligands. Based on the crystal structure information of rat pGC-A ECD with and without rat ANP, a homodimer rotation activation mechanism was proposed for full-length pGC-A, and it was suggested that full-length pGC-A also exists as a homodimer 23 , 25 , 26 .…”