title: Sumoylation modulates 20-hydroxyecdysone signaling by maintaining USP protein levels in Drosophila.
abstract: The nuclear receptor complex for the insect steroid hormone, 20-hydroxyecdysone (20E), is a heterodimer of EcR and USP. It has been shown that Drosophila EcR and USP can be sumoylated in mammalian cells, but it is unknown whether EcR-USP sumoylation naturally occurs in Drosophila. In Drosophila cells, USP, but not EcR, was sumoylated by Smt3, the only Drosophila SUMO protein. The presence of EcR enhanced USP sumoylation, which is further enhanced by 20E treatment. In addition to the Lys20 sumoylation site, five potential acceptor lysine residues in USP were predicted and verified. Mutation of the USP sumoylation sites or reduction of smt3 expression by RNAi attenuated 20E-induced reporter activity. Moreover, in the salivary glands, reducing smt3 expression by RNAi decreased 20E-induced reporter activity, gene expression, and autolysosome formation. Importantly, at least partially, the smt3 RNAi-mediated reduction in 20E signaling resulted from decreased protein levels of USP. In conclusion, sumoylation modulates 20E signaling by maintaining USP protein levels in Drosophila.
authors.affiliation: Key Laboratory of Insect Developmental and Evolutionary Biology, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, 200032, China.
authors.forename: Jiawan
authors.initials: J
authors.lastname: Wang
authors.affiliation: Key Laboratory of Insect Developmental and Evolutionary Biology, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, 200032, China; Division of Neuropathology, School of Medicine, Johns Hopkins University, Baltimore, MD, 21205, USA. Electronic address: tonywang1010@gmail.com.
authors.forename: Sheng
authors.initials: S
authors.lastname: Wang
authors.affiliation: Key Laboratory of Insect Developmental and Evolutionary Biology, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, 200032, China. Electronic address: lisheng01@sibs.ac.cn.
authors.forename: Sheng
authors.initials: S
authors.lastname: Li
mesh_terms: D000818:Animals; D002460:Cell Line; D029721:Drosophila Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D004331:Drosophila melanogaster / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D004441:Ecdysterone / Q000378:metabolism*; D015870:Gene Expression; D006801:Humans; D034622:RNA Interference; D018160:Receptors, Cytoplasmic and Nuclear; D011987:Receptors, Steroid / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D012469:Salivary Glands / Q000378:metabolism; D015398:Signal Transduction; D058207:Sumoylation
chemical_list: D029721:Drosophila Proteins; D018160:Receptors, Cytoplasmic and Nuclear; D011987:Receptors, Steroid; D004441:Ecdysterone
keywords: 20-Hydroxyecdysone; Protein level; Sumoylation; Transcriptional activity; USP