title: Protein kinase C modulates transcriptional activation by the juvenile hormone receptor methoprene-tolerant.
abstract: Juvenile hormone (JH) controls many biological events in insects by triggering dramatic changes in gene expression in target cells. The Methoprene-tolerant (MET) protein, an intracellular JH receptor, acts as a transcriptional regulator and binds to the promoters of tissue- and stage-specific JH target genes when JH is present. Our recent study has demonstrated that the transcriptional activation by MET is modulated by a membrane-initiated JH signaling pathway, involving phospholipase C (PLC) and calcium/calmodulin-dependent protein kinase II (CaMKII). Here we report that protein kinase C (PKC) is another essential intermediate of this pathway. PKC was activated by JH and this action was PLC-dependent. Inhibition of the PKC activity substantially weakened the JH-induced gene expression in mosquito cells. RNAi experiments indicated that several PKC isoforms were involved in the JH action during the post-emergence development of adult female mosquitoes. JH treatment considerably increased the binding of MET to the promoters of JH response genes in cultured mosquito abdomens that were collected from newly emerged female adults. The JH-induced DNA binding of MET was hindered when the abdomens were treated with a PKC inhibitor and JH. Therefore, the results suggest that PKC modulates the transactivation activity of MET by enhancing the binding of MET to JH response elements in the JH target genes. This mechanism may allow for variable and stage- and tissue-specific genomic responses to JH.
authors.affiliation: Department of Biochemistry, Virginia Tech, Blacksburg, VA 24061, USA.
authors.forename: Reyhaneh
authors.initials: R
authors.lastname: Ojani
authors.affiliation: Department of Biochemistry, Virginia Tech, Blacksburg, VA 24061, USA.
authors.forename: Pengcheng
authors.initials: P
authors.lastname: Liu
authors.affiliation: Program of Genetics, Bioinformatics, and Computational Biology, Virginia Tech, Blacksburg, VA 24061, USA.
authors.forename: Xiaonan
authors.initials: X
authors.lastname: Fu
authors.affiliation: Department of Biochemistry, Virginia Tech, Blacksburg, VA 24061, USA. Electronic address: zhujin@vt.edu.
authors.forename: Jinsong
authors.initials: J
authors.lastname: Zhu
mesh_terms: D000330:Aedes; D000818:Animals; D002460:Cell Line; D007605:Juvenile Hormones / Q000378:metabolism / Q000494:pharmacology*; D008726:Methoprene / Q000494:pharmacology*; D011493:Protein Kinase C / Q000378:metabolism*; D011956:Receptors, Cell Surface / Q000378:metabolism*; D015533:Transcriptional Activation / Q000187:drug effects*
chemical_list: D007605:Juvenile Hormones; D011956:Receptors, Cell Surface; D008726:Methoprene; D011493:Protein Kinase C
keywords: Gene regulation; Hormone receptor; Juvenile hormone; Phospholipase C; Protein kinase C