Proposed model of the heterodimeric sGC enzyme complex based on the results of FRET analysis and fusion of sGC subunits.

<p>The dimensions of the domains are given on the basis of the crystal structures of domain homologues (H-NOX, PDB ID 2O09 <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0011617#pone.0011617-Ma1" target="_blank">[9]</a>; PAS, PDB ID 2P04 <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0011617#pone.0011617-Ma2" target="_blank">[13]</a>; cat PDB ID 3ET6 <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0011617#pone.0011617-Winger1" target="_blank">[5]</a>) and the structure of the coiled coil domain of the β<sub>1</sub> subunit (PDB ID 3HLS <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0011617#pone.0011617-Ma3" target="_blank">[18]</a>). Elongated model of the sGC (<b>A</b>). Model according to our results (<b>B</b>). Model of fluorescent-conjoined sGC (<b>C</b>). The β<sub>1</sub> subunit is shown in red and the α subunit is shown in blue. cat - catalytic domain, CC - coiled coil region, PAS - Per-Arnt-Sim fold, HNOX - heme nitric oxide/oxygen binding domain.</p>