Fig. 4From: Comparative genomic analysis suggests that the sperm-specific sodium/proton exchanger and soluble adenylyl cyclase are key regulators of CatSper among the MetazoaDistribution of genes encoding the three proteins in the Arthropoda. Boxes represent the presence of genes as shown in Fig. 1. The phylogenetic tree was prepared based on the Tree of Life Web project (http://www.tolweb.org/tree/). The branching patterns do not represent the proportional evolutionary rateBack to article page