<p>The protein structures were shown in cartoon and colored green and magenta for ERα and ERβ, respectively. E<sub>2</sub> molecules were shown in stick and colored blue and red in ERα and ERβ LBD, respectively. α-Helixes and β-sheets in the ER LBDs are labeled according to references <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0074615#pone.0074615-Brzozowski1" target="_blank">[14]</a>, <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0074615#pone.0074615-Shiau1" target="_blank">[16]</a>. Helix 2 structures are missing in both <i>X</i>-ray structures.</p
