Cloning and characterization of a molt-inhibiting hormone-like peptide from the prawn Marsupenaeus japonicus.

Recently, it was demonstrated by PCR amplification that an additional molt-inhibiting hormone (MIH)-like peptide was present in the kuruma prawn Marsupenaeus japonicus. In this study, a cDNA encoding this peptide designated Pej-MIH-B was cloned. The Pej-MIH-B gene was expressed strongly in the nerve cord, and weakly in the eyestalk. It was possible to isolate Pej-MIH-B from the sinus glands in the eyestalks. The recombinant Pej-MIH-B expressed in Escherichia coli showed low molt-inhibiting activity, but did not exhibit hyperglycemic activity. These results suggest that Pej-MIH-B does not function as MIH or CHH intrinsically, but may have some unknown functions.