title: [E2F1 upregulates endogenous XRCC1 expression].
abstract: OBJECTIVE
  To investigate the regulatory effect and significance of transcription factor E2F1 on X-ray repair cross2 complementing 1 (XRCC1).
  
  
  METHODS
  Saos2 cells were transfected with the E2F1 expression vectors (tet-E2F1) and mutated E2F1 expression vectors (tet-132E). XRCC1 promotor luciferase reporter vector was constructed and transfected into Saos2 cells together with E2F1, E2F2, E2F3 and E2F4 expression vectors at different amount. The cells were collected 36 hours post-transfection for luciferase assays and absorbance was read at 570 nm.
  
  
  RESULTS
  Cotransfection of increasing amounts of E2F1 expression vector with the XRCC1 promoter-luciferase reporter caused a dose-dependent increase in luciferase activation. In contrast, DNA binding incompetent E2F1 (132E) could not activate the XRCC1 promoter-luciferase reporter.
  
  
  CONCLUSIONS
  E2F1 could upregulate endogenous XRCC1 expression and stimulate the XRCC1 promoter.
authors.affiliation: Bejiing Youan Hospital Affiliated to Capital Medical University, Beijing 100069, China.
authors.forename: Juan
authors.initials: J
authors.lastname: Li
authors.forename: Ying
authors.initials: Y
authors.lastname: Shi
authors.forename: Hai-Ying
authors.initials: HY
authors.lastname: Li
authors.forename: Lian-Chun
authors.initials: LC
authors.lastname: Liang
authors.forename: Yun-Xia
authors.initials: YX
authors.lastname: Ji
authors.forename: De-Xi
authors.initials: DX
authors.lastname: Chen
authors.forename: Xin-Yue
authors.initials: XY
authors.lastname: Chen
authors.forename: Hao
authors.initials: H
authors.lastname: Wu
mesh_terms: D045744:Cell Line, Tumor; D004268:DNA-Binding Proteins / Q000235:genetics* / Q000378:metabolism; D050687:E2F1 Transcription Factor / Q000235:genetics / Q000378:metabolism*; D015870:Gene Expression; D017930:Genes, Reporter; D006801:Humans; D011401:Promoter Regions, Genetic; D011485:Protein Binding; D015854:Up-Regulation; D000076105:X-ray Repair Cross Complementing Protein 1
chemical_list: D004268:DNA-Binding Proteins; D050687:E2F1 Transcription Factor; C493753:E2F1 protein, human; D000076105:X-ray Repair Cross Complementing Protein 1; C000619371:XRCC1 protein, human