Molecular cloning of a molt-inhibiting hormone cDNA from the kuruma prawn Penaeus japonicus.
The crustacean molt-inhibiting hormone (MIH) is released from the X-organ sinus gland complex and suppresses ecdysteroid synthesis by the Y-organ. In the present study, we have isolated a cDNA which encodes a MIH (Pej-SGP-IV) of the kuruma prawn Penaeus japonicus in order to study its expression and characterize the structure of its precursor. A cDNA fragment was isolated using RT-PCR with two degenerate oligonucleotide primers that were designed based on the peptide sequence of Pej-SGP-IV, and this fragment was used as a probe to screen an eyestalk cDNA library. In a positive cDNA clone (814 base pairs (bp)), an open reading frame of 315 bp was found; the conceptually translated protein consists of a putative signal peptide (28 residues) and Pej-SGP-IV (77 residues). In Northern blot analysis using a cDNA probe, specific hybridization to a transcript of 0.95 kb was seen in RNA extracted from the eyestalk but not from hepatopancreas, abdominal muscle, brain, thoracic ganglia or abdominal ganglia. The level of the Pej-SGP-IV mRNA in the eyestalk did not change significantly during the molt cycle.
Ohira
T
T
Department of Aquatic Bioscience, Graduate School of Agricultural and Life Sciences, University of Tokyo, Japan.
Watanabe
T
T
Nagasawa
H
H
Aida
K
K
D000818:Animals; D001483:Base Sequence; D015152:Blotting, Northern; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000235:genetics*; D005786:Gene Expression Regulation; D007447:Invertebrate Hormones / Q000032:analysis / Q000235:genetics*; D008969:Molecular Sequence Data; D018978:Molting / Q000502:physiology; D033561:Penaeidae / Q000235:genetics*; D012313:RNA; D014018:Tissue Distribution
D018076:DNA, Complementary; D007447:Invertebrate Hormones; C012445:molt-inhibiting hormone; D012313:RNA