APH-1, a POU homeobox gene expressed in the salt gland of the crustacean Artemia franciscana

We characterized the first POU-homeoprotein in a crustacean (designated APH -1 for Artemia POU-Homeoprotein, EMBL Y15070). The amino acid sequence of t he APH-1 POU-domain is identical, except for two residues, to that of the t wo class III POU proteins Cf1-a (Drosophila) and POU-M1 (Bombyx mori). Sout hern blot analysis suggests that crustaceans have only one class III POU ge ne. RT-PCR and whole-mount in situ hybridization show that APH-1 mRNA is pr esent in larvae specifically in the salt gland, an organ which is involved in osmoregulation, and disappears in the adult. (C) 1999 Elsevier Science I reland Ltd. All rights reserved.