Overview on the sub-grouping of the crustacean hyperglycemic hormone family

The Crustacean hyperglycemic hormones (CHHs) are an ever extending family o f crustacean hormones mainly involved in carbohydrate metabolism, molt and reproduction. In this paper, we drew together 32 available CHH sequences, a nd applied the techniques of multiple sequence alignment, motif searching a nd amino acid conservation analysis to the characterization of the molecule s independently of their biological function. The analysis clearly showed t hat the proteins clustered into two groups (CHH and VIH). Amino acid conser vation analysis also subdivided the VIH group into sequences involved in re production (RIH) or in molt (MIH). Motif searching identified five motifs i n each group of mature hormones. Motifs A2 and A3 were conserved in all seq uences while motifs Al and A1' were specific of the CHH and VIH groups resp ectively. This approach demonstrated the S. gregaria ion transport peptides as true members of the CHH group. The two main groups, CHH and VIH, are al so discussed in terms of functional homogeneity.