title: The RING finger protein RNF4, a co-regulator of transcription, interacts with the TRPS1 transcription factor.
abstract: The TRPS1 gene encodes a repressor of GATA-mediated transcription. Mutations in this gene cause the tricho-rhino-phalangeal syndromes, but the affected pathways are unknown. In a yeast two-hybrid screen with the C-terminal part of the murine Trps1 protein as bait, we obtained three yeast clones encoding two overlapping fragments of the 194 amino acids RING finger protein 4 (Rnf4). The overlap narrows down the Trps1-binding region within Rnf4 to amino acids 6-65. This region in Rnf4 is also known to interact with several proteins including steroid receptors. By using truncated Trps1 constructs, the Rnf4-binding region in Trps1 could be assigned to amino acids 985-1184 of 1281. This 200 amino acid region of Trps1 does not contain any predicted protein-protein interacting motif. Complex formation between the human proteins TRPS1 and RNF4 was verified by co-immunoprecipitation from transfected and native mammalian cells. Confocal laser-scanning microscopy revealed that the endogenous proteins are located in distinct structures of the nucleus. Using a luciferase reporter assay, we could demonstrate that the repressional function of TRPS1 is inhibited by RNF4. This finding suggests that RNF4 is a negative regulator of TRPS1 activity.
authors.affiliation: Institut für Humangenetik, Universitätsklinikum, Hufelandstrasse 55, D-45122 Essen, Germany.
authors.forename: Frank J
authors.initials: FJ
authors.lastname: Kaiser
authors.forename: Tarik
authors.initials: T
authors.lastname: Möröy
authors.forename: Glenn T G
authors.initials: GT
authors.lastname: Chang
authors.forename: Bernhard
authors.initials: B
authors.lastname: Horsthemke
authors.forename: Hermann-Josef
authors.initials: HJ
authors.lastname: Lüdecke
mesh_terms: D020816:Amino Acid Motifs; D000596:Amino Acids / Q000737:chemistry; D000818:Animals; D015153:Blotting, Western; D019556:COS Cells; D002467:Cell Nucleus / Q000378:metabolism; D002478:Cells, Cultured; D018076:DNA, Complementary / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000378:metabolism*; D005786:Gene Expression Regulation; D017930:Genes, Reporter; D006801:Humans; D008156:Luciferases / Q000378:metabolism; D051379:Mice; D018613:Microscopy, Confocal; D008856:Microscopy, Fluorescence; D008957:Models, Genetic; D009154:Mutation; D009363:Neoplasm Proteins; D009687:Nuclear Proteins / Q000378:metabolism*; D011233:Precipitin Tests; D011485:Protein Binding; D017434:Protein Structure, Tertiary; D012097:Repressor Proteins; D014157:Transcription Factors; D014158:Transcription, Genetic; D014162:Transfection; D020798:Two-Hybrid System Techniques; D044767:Ubiquitin-Protein Ligases; D001616:beta-Galactosidase / Q000378:metabolism
chemical_list: D000596:Amino Acids; D018076:DNA, Complementary; D004268:DNA-Binding Proteins; D009363:Neoplasm Proteins; D009687:Nuclear Proteins; C114070:RNF4 protein, human; D012097:Repressor Proteins; C108387:TRPS1 protein, human; D014157:Transcription Factors; D008156:Luciferases; C486410:Rnf4 protein, mouse; D044767:Ubiquitin-Protein Ligases; D001616:beta-Galactosidase