MOLECULAR-CLONING OF 2 PIGMENT-DISPERSING HORMONE (PDH) PRECURSORS INTHE BLUE-CRAB CALLINECTES-SAPIDUS REVEALS A NOVEL MEMBER OF THE PDH NEUROPEPTIDE FAMILY

A cDNA library was established from the eyestalk ganglia of the blue c rab Callinectes sapidus. Screening resulted in the isolation of a clon e (497 bp excluding poly(A) tail) which encodes a beta-PDH previously found in several crustacean species. It displays high sequence similar ity with a clone isolated from an eyestalk cDNA library of the shore c rab Carcinus maenas, indicating the close phylogenetic relationship of both species. A second clone (414 bp exclusive of the poly(A) tail) e ncodes a novel beta-PDH analog which displays 400-fold less potency in crab bioassays. Both cDNAs encode open reading frames of 234 bp for t he prepropeptides, consisting of signal peptides, PDH-precursor-relate d peptides, and PDH sequences. (C) 1994 Academic Press, Inc.