Schematic representation of the six Sus gene structures in citrus.

<p>Boxes indicate exons and single lines between the boxes indicate introns. The numbers on boxes and down lines indicate the length of the exon and intron, respectively. Sus I, II and III refer to the three groups of Sus genes family shown in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0113623#pone-0113623-g002" target="_blank">Figure 2</a>.