title: Transcriptional ERRgamma2-mediated activation is regulated by sentrin-specific proteases.
abstract: Modification with SUMOs (small ubiquitin-related modifiers) has emerged as an important means of regulating the activity of transcription factors, often by repressing their activity. The ERRgamma [oestrogen receptor-related receptor gamma; ERR3 or NR3B3 (nuclear receptor subfamily 3, group B, gene3)] is a constitutively active orphan nuclear receptor. A PDSM, (phosphorylation-dependent sumoylation motif) is located in the close vicinity of the N-terminally located ERRgamma2-specific AF-1 (activation function-1). Its function can be replaced by an NDSM (negatively charged amino acid-dependent sumoylation motif). A mutational analysis reveals that ERRgamma2 activity is modulated through sumoylation of a lysine residue at position 40, which in turn is regulated by phosphorylation. Phosphorylation at the +5 position relative to the sumoylation target is directly visualized by a high-resolution EMSA (electrophoretic mobility-shift assay). Sumoylation represses the activity of ERRgamma both with and without forced expression of the PGC-1beta (peroxisome-proliferator-activated receptor gamma co-activator-1beta). Fusion proteins of a heterologous DNA-binding domain with the ERRgamma2 N-terminus demonstrate the function of the PDSM as the RF-1 (repression function-1) for the neighbouring AF-1. De-repression is achieved by co-expression of sentrin/SENP (sentrin-specific protease) family members. Together, our results demonstrate reversible phosphorylation-dependent sumoylation as a means to regulate the activity of an orphan nuclear receptor.
authors.affiliation: Zentrum für Molekulare Neurobiologie, Universitätsklinikum Hamburg-Eppendorf, Martinistrasse 52, 20246 Hamburg, Germany.
authors.forename: Moritz
authors.initials: M
authors.lastname: Hentschke
authors.forename: Ute
authors.initials: U
authors.lastname: Süsens
authors.forename: Uwe
authors.initials: U
authors.lastname: Borgmeyer
mesh_terms: D000818:Animals; D002460:Cell Line; D045744:Cell Line, Tumor; D003546:Cysteine Endopeptidases; D024202:Electrophoretic Mobility Shift Assay; D006801:Humans; D051379:Mice; D009097:Multienzyme Complexes / Q000378:metabolism*; D009154:Mutation; D010766:Phosphorylation; D011960:Receptors, Estrogen / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D025841:Small Ubiquitin-Related Modifier Proteins / Q000378:metabolism; D014158:Transcription, Genetic / Q000235:genetics; D015533:Transcriptional Activation / Q000235:genetics
chemical_list: D009097:Multienzyme Complexes; D011960:Receptors, Estrogen; D025841:Small Ubiquitin-Related Modifier Proteins; D003546:Cysteine Endopeptidases; C439066:Senp2 protein, mouse