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Negative regulation of the mammalian UV response by Myc through association with Miz-1

Steffi Herold1, Michael Wanzel, Vincent Beuger

  • 1Institute for Molecular Biology and Tumor Research, 35033 Marburg, Germany.

Molecular Cell
|November 1, 2002
PubMed

Insights

The Myc oncoprotein and Miz-1 transcription factor regulate cell proliferation after UV damage. UV irradiation releases Miz-1, upregulating p21Cip1 and aiding cell cycle recovery.

Area of Science:

  • Molecular Biology
  • Cell Biology
  • Oncology

Background:

  • The Myc oncoprotein is known to repress transcription via the Miz-1 transcription factor.
  • Understanding the regulation of cell cycle progression following DNA damage is crucial for cancer research.

Purpose of the Study:

  • To investigate the role of Miz-1 and its interaction with TopBP1 in regulating p21Cip1 expression and cell cycle arrest after UV irradiation.
  • To elucidate the mechanism by which Myc influences UV-induced cell cycle arrest.

Main Methods:

  • In vivo promoter binding assays
  • UV irradiation experiments
  • Analysis of c-myc knockout and mutant cells

Main Results:

  • UV irradiation downregulates TopBP1, releasing Miz-1.
  • Miz-1 binds to the p21Cip1 promoter and is essential for its upregulation post-UV.
  • Myc negatively regulates p21Cip1 transcription and promotes recovery from UV-induced cell cycle arrest by interacting with Miz-1.

Conclusions:

  • Miz-1 plays a critical role in the cellular response to UV irradiation by regulating p21Cip1 expression.
  • The Myc-Miz-1 interaction is implicated in controlling cell proliferation and recovery following UV-induced DNA damage.

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