PMID: 23136906 RLIMS-P 7 Check other iTextMine results Issue Report
Title
| 1. | PKC-mediated USP phosphorylation at Ser35 modulates 20-hydroxyecdysone signaling in Drosophila. |
Abstract
| 2. | The nuclear receptor complex of the steroid hormone, 20-hydroxyecdysone (20E), is a heterodimer composed of EcR and USP. |
| 3. | Our previous studies in Drosophila suggest that PKC modulates 20E signaling by phosphorylating EcR-USP. |
| 4. | However, the exact phosphorylation sites in EcR and USP have not been identified. |
| 5. | Using LC-MS/MS analysis, we first identified Ser35 of USP as a PKC phosphorylation site. |
| 6. | Mutation of USP Ser35 to Ala35 in S2 cells not only eliminated USP phosphorylation, but also attenuated the 20E-induced luciferase activity, mimicking the treatment with a PKC-specific inhibitor chelerythrine chloride in Kc cells. |
| 7. | In the larval salivary glands (SG), inhibition of PKC activity with the binary GAL4/UAS system reduced USP phosphorylation and down-regulated the 20E primary-response genes, E75B and Br-C, and RNAi knockdown of Rack1 had stronger inhibitory effects than overexpression of PKCi. |
| 8. | Moreover, RNAi knockdown of four PKC isozyme genes expressed in the SG exhibited a variety of inhibitory effects on USP phosphorylation and expression of E75B and Br-C, with the strongest inhibitory effects occurring when aPKC was knocked down by RNAi. |
| 9. | Taken together, we conclude that PKC-mediated USP phosphorylation at Ser35 modulates 20E signaling in Drosophila. |
Loading...
Loading data