Regulation of the Ets-1 transcription factor by sumoylation and ubiquitinylation.
Sumoylation and ubiquitinylation reversibly regulate the activity of transcription factors through covalent attachment to lysine residues of target proteins. We examined whether the Ets-1 transcription factor is modified by sumoylation and/or ubiquitinylation. Among four potential SUMO motifs in Ets-1, we identified lysines 15 and 227 within the LK(15)YE and IK(227)QE motifs, as being the sumoylation acceptor sites. Using transfection of Ets-1 wildtype (WT) or its sumoylation deficient version (Ets-1 K15R/K227R), as well as WT or mutant proteins of the SUMO pathway, we further demonstrated that the E2 SUMO-conjugating enzyme Ubc9 and a E3 SUMO ligase, PIASy, can enhance Ets-1 sumoylation, while a SUMO protease, SENP1, can desumoylate Ets-1. We also found that Ets-1 is modified by K48-linked polyubiquitinylation independently of the sumoylation acceptor sites and is degraded through the 26S proteasome pathway, while sumoylation of Ets-1 does not affect its stability. Finally, sumoylation of Ets-1 leads to reduced transactivation and we demonstrated that previously identified critical lysine residues in Synergistic Control motifs are the sumoylation acceptor sites of Ets-1. These data show that Ets-1 can be modified by sumoylation and/or ubiquitinylation, with sumoylation repressing transcriptional activity of Ets-1 and having no clear antagonistic action on the ubiquitin-proteasome degradation pathway.
Ji
Z
Z
UMR 8161, Institut de Biologie de Lille, CNRS, Institut Pasteur de Lille, Université de Lille 1, Université de Lille 2, Lille Cedex, France.
Degerny
C
C
Vintonenko
N
N
Deheuninck
J
J
Foveau
B
B
Leroy
C
C
Coll
J
J
Tulasne
D
D
Baert
J-L
JL
Fafeur
V
V
D000818:Animals; D019556:COS Cells; D002460:Cell Line; D002522:Chlorocebus aethiops; D004285:Dogs; D006801:Humans; D015151:Immunoblotting; D047468:Immunoprecipitation; D007668:Kidney / Q000378:metabolism; D008156:Luciferases / Q000235:genetics / Q000378:metabolism; D011499:Protein Processing, Post-Translational; D050784:Proto-Oncogene Protein c-ets-1 / Q000235:genetics / Q000378:metabolism*; D011817:Rabbits; D025842:SUMO-1 Protein / Q000378:metabolism*; D014158:Transcription, Genetic; D025801:Ubiquitin / Q000378:metabolism*; D044763:Ubiquitin-Conjugating Enzymes / Q000378:metabolism
D050784:Proto-Oncogene Protein c-ets-1; D025842:SUMO-1 Protein; D025801:Ubiquitin; D008156:Luciferases; D044763:Ubiquitin-Conjugating Enzymes