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Stealing the spotlight: CUL4-DDB1 ubiquitin ligase docks WD40-repeat proteins to destroy

Leigh Ann Higa1, Hui Zhang

  • 1Yale University School of Medicine, Department of Genetics, 333 Cedar Street, New Haven, Connecticut 06520, USA. leighann.higa@yale.edu

Cell Division
|February 7, 2007
PubMed

Insights

Cullin 4 (CUL4) ubiquitin ligases regulate key cellular processes like DNA repair and gene expression. New research highlights their architecture and roles in genome stability and cell cycle control.

Area of Science:

  • Molecular Biology
  • Cell Biology
  • Biochemistry

Background:

  • Cullin 4 (CUL4) is a key component of multiprotein ubiquitin E3 ligases.
  • These ligases regulate critical cellular processes including DNA repair, cell cycle, and gene expression.
  • CUL4 functions by associating with DNA Damage Binding protein 1 (DDB1) to form an E3 ligase complex.

Purpose of the Study:

  • To review recent advancements in understanding the mechanism of CUL4 ubiquitin E3 ligase.
  • To discuss the structural architecture of CUL4-assembled E3 ubiquitin ligase complexes.
  • To highlight the roles of CUL4 ligase in genome stability, cell cycle regulation, and histone methylation.

Main Methods:

  • Review of recent scientific literature on CUL4 ubiquitin E3 ligase.
  • Comparative analysis of CUL4-based E3 ligases with CUL1-based SCF complexes.
  • Examination of specific examples demonstrating CUL4 ligase functions.

Main Results:

  • CUL4-DDB1 complexes utilize WD40-repeat proteins (WDR) as substrate-recognition subunits.
  • Over 150-300 WDR proteins in the human genome suggest broad biological impact of CUL4 ligases.
  • CUL4 ligase activity is modulated by neddylation and the COP9 signalosome complex (CSN).

Conclusions:

  • CUL4 ubiquitin E3 ligases are crucial regulators of fundamental biological processes.
  • Understanding CUL4 complex architecture provides insights into substrate targeting and ligase activity.
  • This ligase system plays vital roles in maintaining genome stability and controlling cell cycle progression.

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