Synergistic cooperation of MDM2 and E2F1 contributes to TAp73 transcriptional activity

Journal Article · Fri Jul 04 04:00:00 EDT 2014 · Biochemical and Biophysical Research Communications

DOI:https://doi.org/10.1016/J.BBRC.2014.05.026· OSTI ID:22416604

Kasim, Vivi ^[1]; Huang, Can; Zhang, Jing; Jia, Huizhen; Wang, Yunxia ^[1]; Yang, Li ^[1]; Miyagishi, Makoto ^[2]; Wu, Shourong ^[1]

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1. The Key Laboratory of Biorheological Science and Technology, Ministry of Education, College of Bioengineering, Chongqing University, Chongqing 400044 (China)
2. Molecular Composite Medicine Research Group, Biomedical Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba 305-8566 (Japan)

Highlights: • MDM2 is a novel positive regulator of TAp73 transcriptional activity. • MDM2 colocalizes together and physically interacts with E2F1. • Synergistic cooperation of MDM2 and E2F1 is crucial for TAp73 transcription. • MDM2 regulates TAp73 transcriptional activity in a p53-independent manner. - Abstract: TAp73, a structural homologue of p53, plays an important role in tumorigenesis. E2F1 had been reported as a transcriptional regulator of TAp73, however, the detailed mechanism remains to be elucidated. Here we reported that MDM2-silencing reduced the activities of the TAp73 promoters and the endogenous TAp73 expression level significantly; while MDM2 overexpression upregulated them. We further revealed that the regulation of TAp73 transcriptional activity occurs as a synergistic effect of MDM2 and E2F1, most probably through their physical interaction in the nuclei. Furthermore, we also suggested that MDM2 might be involved in DNA damage-induced TAp73 transcriptional activity. Finally, we elucidated that MDM2-silencing reduced the proliferation rate of colon carcinoma cells regardless of the p53 status. Our data show a synergistic effect of MDM2 and E2F1 on TAp73 transcriptional activity, suggesting a novel regulation pathway of TAp73.

• OSTI ID: 22416604
• Journal Information: Biochemical and Biophysical Research Communications, Journal Name: Biochemical and Biophysical Research Communications Journal Issue: 3 Vol. 449; ISSN 0006-291X; ISSN BBRCA9
• Country of Publication: United States
• Language: English

Related Subjects

60 APPLIED LIFE SCIENCES
CARCINOMAS
CELL NUCLEI
CELL PROLIFERATION
COOPERATION
DNA DAMAGES
LARGE INTESTINE
PROMOTERS
REGULATIONS
TRANSCRIPTION
TRANSCRIPTION FACTORS