title: The DEAD box protein DP103 is a regulator of steroidogenic factor-1.
abstract: The nuclear receptor steroidogenic factor-1 (SF-1) is essential for development of the gonads, adrenal gland, and the ventromedial hypothalamic nucleus. It also regulates the expression of pivotal steroidogenic enzymes and other important proteins in the reproductive system. We sought to elucidate the mechanisms that govern the transcriptional activity of SF-1. We demonstrate here that a previously uncharacterized domain, located C-terminal to the DNA binding domain of SF-1, exhibits transcriptional repression function. Point mutations in this domain markedly potentiate the transcriptional activity of native SF-1. Using an SF-1 region that spans this proximal repression domain as bait in a yeast two-hybrid system, we cloned an SF-1 interacting protein that is homologous to human DP103, a member of the DEAD box family of putative RNA helicases. DP103 directly interacts with the proximal repression domain of SF-1, and mutations in this domain abrogate its interaction with DP103. DP103 is expressed predominantly in the testis and is also expressed at a lower level in other steroidogenic and nonsteroidogenic tissues. Functionally, DP103 exhibits a native transcriptional repression function that localizes to the C-terminal region of the protein and represses the activity of wild-type, but not mutant, SF-1. Together, the physical and functional interaction of DP103 with a previously unrecognized repression domain within SF-1 represents a novel mechanism for regulation of SF-1 activity.
authors.affiliation: Department of Obstetrics and Gynecology, Washington University School of Medicine St. Louis, Missouri 63110, USA.
authors.forename: Q
authors.initials: Q
authors.lastname: Ou
authors.forename: J F
authors.initials: JF
authors.lastname: Mouillet
authors.forename: X
authors.initials: X
authors.lastname: Yan
authors.forename: C
authors.initials: C
authors.lastname: Dorn
authors.forename: P A
authors.initials: PA
authors.lastname: Crawford
authors.forename: Y
authors.initials: Y
authors.lastname: Sadovsky
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001665:Binding Sites; D002460:Cell Line; D003001:Cloning, Molecular; D055541:DEAD Box Protein 20; D053487:DEAD-box RNA Helicases; D004247:DNA / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D005260:Female; D051717:Fushi Tarazu Transcription Factors; D015870:Gene Expression; D018398:Homeodomain Proteins; D006801:Humans; D008297:Male; D051379:Mice; D008969:Molecular Sequence Data; D017354:Point Mutation; D020365:RNA Helicases / Q000235:genetics / Q000494:pharmacology / Q000502:physiology*; D051381:Rats; D018160:Receptors, Cytoplasmic and Nuclear; D011993:Recombinant Fusion Proteins / Q000737:chemistry / Q000378:metabolism; D012097:Repressor Proteins / Q000494:pharmacology / Q000502:physiology; D017385:Sequence Homology; D054339:Steroidogenic Factor 1; D014157:Transcription Factors / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D014158:Transcription, Genetic / Q000187:drug effects; D014162:Transfection
chemical_list: D004268:DNA-Binding Proteins; D051717:Fushi Tarazu Transcription Factors; D018398:Homeodomain Proteins; C515057:NR5A1 protein, human; D018160:Receptors, Cytoplasmic and Nuclear; D011993:Recombinant Fusion Proteins; D012097:Repressor Proteins; D054339:Steroidogenic Factor 1; D014157:Transcription Factors; C515058:steroidogenic factor 1, mouse; C515060:steroidogenic factor 1, rat; D004247:DNA; C120168:DDX20 protein, human; D055541:DEAD Box Protein 20; C485624:Ddx20 protein, mouse; D053487:DEAD-box RNA Helicases; D020365:RNA Helicases