A comparison between membrane-embedded, dimeric models of TPO isoform1 in two different conformations.

<p><b>(A)</b> Schematic of trans model with active site facing away from follicular membrane. Coloring as in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0142615#pone.0142615.g001" target="_blank">Fig 1</a>; <b>(B)</b> Cis model with active site facing towards follicular membrane; <b>(C)</b> perpendicular views of trans model; <b>(D)</b> perpendicular views of cis model. TPO represented as cartoon and space filling (subunits A and B, respectively) for clarity. Domains are coloured as follows: MPO-like domain (green), CCP-like domain (Shamrock green), EGF-like domain (cyan-blue), and TM domain (dark-blue). Catalytic heme represented as red spheres, and DMPC molecules represented as lines and coloured as CPK.</p>