Proteomic identification of PKC-mediated expression of 20E-induced protein in Drosophila melanogaster.
Ecdysone receptor (EcR) and its heterodimeric partner, ultraspiracle protein (USP), are nuclear receptors that mediate the action of the insect molting hormone 20-hydroxyecdysone (20E). There is evidence that the activity of both receptors is affected by phosphorylation. Using a proteomic approach, we have shown that protein kinase C (PKC) activity is necessary for mediating 20E-induced expression of 14 specific proteins, including three previously reported 20E responsive proteins, and is also responsible for the intracellular localization of EcR and USP in larval salivary glands of Drosophila melanogaster. The 20E-dependent expression of the proteins was verified using real-time PCR and/or Western blot analysis. For some genes, inhibition of PKC activity reduced 20E-dependent transcriptional activity rapidly, raising the possibility that these are direct gene targets of EcR and USP. The data further indicate that PKC-mediated phosphorylation is also required for genes regulated indirectly by 20E-induced changes in the larval salivary gland.
Sun
Yaning
Y
Division of Plant Sciences, 1-31 Agriculture Building, University of Missouri, Columbia, Missouri 65211, USA.
An
Shiheng
S
Henrich
Vincent C
VC
Sun
Xiaoping
X
Song
Qisheng
Q
D000818:Animals; D015153:Blotting, Western; D002467:Cell Nucleus / Q000378:metabolism; D003600:Cytosol / Q000378:metabolism; D019281:Dimerization; D004305:Dose-Response Relationship, Drug; D004331:Drosophila melanogaster; D004441:Ecdysterone / Q000378:metabolism*; D015971:Gene Expression Regulation, Enzymologic; D010766:Phosphorylation; D011493:Protein Kinase C / Q000378:metabolism*; D040901:Proteomics / Q000379:methods*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D014158:Transcription, Genetic
D004441:Ecdysterone; D011493:Protein Kinase C