Isolation and expression analysis of a Pax group III gene from the crustacean Cherax destructor.

Pax genes encode transcription factors that are critical regulators of key developmental processes in evolutionarily diverse animal phyla. Here we report the first isolation of a Pax gene from a crustacean: a Pax group III gene we have termed CdpaxIII that contains highly conserved DNA-binding domains, the paired domain and homeodomain. CdpaxIII is expressed in the embryo, in adult limb muscle during both quiescence and regeneration, and during the distinct process of epimorphic limb regeneration. Interestingly, CdpaxIII is expressed as two distinct alternate transcripts, one of which is novel in lacking a large portion of its paired domain.