Functional variability across mole-rat OR7 receptors (redrawn from [15]).

<p>Functional variation is colour coded based on the number of different amino-acids presents at each position: red – highly variable (≥5); orange – variable (3–4); light blue – conserved (2); dark blue – highly conserved (1). Amino-acid positions involved odorant-binding are circled in black <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0093336#pone.0093336-Man1" target="_blank">[14]</a>, <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0093336#pone.0093336-Katada1" target="_blank">[15]</a>; these are predominantly variable in our dataset, as expected. Abbreviations stand for the following: TM trans-membrane domain, EC extra-cellular and IC intracellular domain.