Inhibitory effect of molt-inhibiting hormone onphantomexpression in the Y-organ of the kuruma prawn,Marsupenaeus japonicus
| Autor: | Shinji Nagata, Hiromichi Nagasawa, Hideaki Asazuma |
|---|---|
| Rok vydání: | 2009 |
| Předmět: |
medicine.medical_specialty
DNA Complementary animal structures Invertebrate Hormones Physiology Amino Acid Motifs Molecular Sequence Data Gene Expression Biology Biochemistry Halloween genes chemistry.chemical_compound Cytochrome P-450 Enzyme System Penaeidae Sequence Analysis Protein Internal medicine Complementary DNA Gene expression Hemolymph medicine Animals Cloning Molecular Phylogeny Regulation of gene expression Ecdysteroid Base Sequence Reverse Transcriptase Polymerase Chain Reaction fungi Ecdysteroids Gene Expression Regulation Developmental General Medicine Cell biology Endocrinology chemistry Insect Science Ecdysis Sequence Alignment Moulting |
| Zdroj: | Archives of Insect Biochemistry and Physiology. 72:220-233 |
| ISSN: | 1520-6327 0739-4462 |
| Popis: | Molting in crustaceans is induced by ecdysteroids as in insects. The ecdysteroid titre in hemolymph is negatively regulated by molt-inhibiting hormone (MIH) that inhibits the secretion of ecdysteroids from the Y-organ, an ecdysteroid-producing gland of crustaceans, whereas little is known about the molecular mechanism of inhibition by MIH. Recently, the Halloween genes encoding cytochrome P450 monooxygenases were characterized as the steroidogenic enzymes in insects. To elucidate whether the ecdysteroidogenesis in the Y-organ is regulated by molt-inhibiting hormone (MIH), we analyzed the expression level of an orthologue of a member of the Halloween genes, phantom (Cyp306a1, phm), in the Y-organ of a decapod crustacean, Marsupenaeus japonicus. A cDNA encoding phm (Mj-phm) was cloned by degenerate PCR and 5'- and 3'-RACEs. The deduced amino acid sequence of Mj-phm showed about 40% identity to those of insect phm. The six motif sequences and the four substrate recognition sites were well conserved between Mj-PHM and other PHM. RT-PCR showed the specific expression of Mj-phm mRNA in the Y-organ. In addition, quantitative real-time PCR verified that the expression level of Mj-phm was significantly increased at the pre-molt stage and decreased after ecdysis. Furthermore, exposure of the Y-organ to MIH significantly decreased the Mj-phm expression level in vitro. These results indicate that the transcription of Mj-phm in the Y-organ may be regulated by the inhibitory mechanism of MIH of M. japonicus, which involves the consequent negative regulation of ecdysteroidogenesis at the transcriptional level. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Plný text