RAP80 interacts with the SUMO-conjugating enzyme UBC9 and is a novel target for sumoylation

Academic Article


  • RAP80, a nuclear protein with two functional ubiquitin-interaction motifs (UIMs) at its N-terminus, plays a critical role in the regulation of estrogen receptor alpha and DNA damage response signaling. A yeast two-hybrid screen identified the SUMO-conjugating enzyme UBC9 as a protein interacting with RAP80. The interaction of RAP80 with UBC9 was confirmed by co-immunoprecipitation and GST pull-down analyses. The region between aa 122-204 was critical for the interaction of RAP80 with UBC9. In addition, we demonstrate that RAP80 is a target for SUMO-1 modification in intact cells. Expression of UBC9 enhanced RAP80 mono-sumoylation and also induced multi-sumoylation of RAP80. In addition to SUMO-1, RAP80 was efficiently conjugated to SUMO-3 but was only a weak substrate for SUMO-2 conjugation. These findings suggest that sumoylation plays a role in the regulation of RAP80 functions.
  • Digital Object Identifier (doi)

    Pubmed Id

  • 9371637
  • Author List

  • Yan J; Yang XP; Kim YS; Joo JH; Jetten AM
  • Start Page

  • 132
  • End Page

  • 138
  • Volume

  • 362
  • Issue

  • 1