Molecular cloning of a cDNA encoding a member of CHH/MIH/GIH family from Penaeus monodon and analysis of its gene structure

We report the nucleotide and deduced amino acid sequences of Pem-CMG peptid e, a member of crustacean CHH/MIH/GM peptide family, in black tiger prawn ( Penaeus monodon). The 5' and 3' fragments of Pem-CMG cDNA were cloned by th e method of rapid amplification of cDNA ends (RACE). The two fragments cons titute a combined cDNA length of 593 bp with a 77 bp overlapping region. Se quence analysis reveals the presence of a 384 bp open reading frame which w as subsequently cloned. The open reading frame encodes a precursor peptide that is comprised of 128 amino acids, with a putative processing site, KR. The mature peptide consists of 74 amino acid residues, the sequence of whic h is significantly homologous to those of the CHH/MIH/GM family known from other crustaceans. Analysis of a genomic fragment of Pem-CMG reveals a sing le intron of 314 bp interrupting the coding sequence for the mature peptide . The presence of only one intron in Pem-CMG gene suggests that this gene i s structurally different from the previously reported MIN gene of Charybdis feriatus and CHH-like gene of Metapenaeus ensis which possess two introns in their coding sequences. (C) 2000 Elsevier Science B.V. All rights reserv ed.