LIUBICICH, Danielle M.*; SERANO, Julia M.; PATEL, Nipam H.; University of California, Berkeley; University of California, Berkeley; University of California, Berkeley: The role of Hox genes in crustacean appendage diversity

Crustaceans display extraordinary diversity in appendage morphology and body regionalization. Although these animals display many unique morphological characteristics, they utilize patterning mechanisms conserved among all arthropods. Hox genes are members of a highly conserved family of transcription factors that are involved in regionalization of animal body plans, and recent studies have shown that changes in Hox gene expression patterns between crustacean species correlate with evolutionary changes in appendage identity. The expression pattern of one particular Hox gene, Ultrabithorax (Ubx) shows a correlation with the boundary between segments bearing maxilliped versus non-maxilliped appendages in the thorax. We have cloned orthologs of each of the eight major Drosophila Hox genes in the amphipod crustacean Parhyale hawaiensis. To further investigate the role of Hox genes in appendage development and evolution, we have focused on understanding the role of Ubx, Antennapedia (Antp), and Sex-combs reduced (Scr) in Parhyale, and are currently attempting functional experiments through the knockdown of gene expression by morpholino and RNAi techniques.