DDB1 functions as a linker to recruit receptor WD40 proteins to CUL4-ROC1 ubiquitin ligases

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Using In Vitro Fluorescence Resonance Energy Transfer to Study the Dynamics Of Protein Complexes at a Millisecond Time Scale
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Using In Vitro Fluorescence Resonance Energy Transfer to Study the Dynamics Of Protein Complexes at a Millisecond Time Scale

Published on: March 14, 2019

Yizhou Joseph He1, Chad M McCall, Jian Hu

  • 1Lineberger Comprehensive Cancer Center, Department of Biochemistry and Biophysics, Program in Molecular Biology and Biotechnology, University of North Carolina, Chapel Hill, NC 27599, USA.

Genes & Development
|November 3, 2006
PubMed

Insights

Researchers identified a novel protein motif, the DWD box, crucial for substrate recruitment in CUL4A ubiquitin ligases. This discovery reveals DDB1

Area of Science:

  • Molecular Biology
  • Biochemistry
  • Cellular Biology

Background:

  • Cullin-RING complexes are the largest family of E3 ubiquitin ligases, essential for protein degradation.
  • CUL4A, a key component, plays roles in various cellular processes, but its substrate recognition mechanism is not fully understood.

Purpose of the Study:

  • To elucidate the substrate-recruiting mechanism of CUL4A ubiquitin ligases.
  • To identify novel protein motifs and interactions involved in CUL4A substrate targeting.

Main Methods:

  • Protein motif identification and characterization.
  • Co-immunoprecipitation assays to demonstrate protein-protein interactions.
  • Database searches for motif prevalence.

Main Results:

  • A novel DWD (DDB1-binding WD40) box motif was identified.
  • Fifteen DWD proteins were shown to bind with DDB1-CUL4A complex.
  • The DWD box and DDB1 were confirmed as critical for linking DWD proteins to CUL4A.

Conclusions:

  • The DWD box is a key motif for substrate recruitment in DDB1-CUL4A ligases.
  • DDB1 acts as a crucial linker protein between DWD proteins and the CUL4A core complex.
  • A significant portion of WD40 proteins may contain DWD boxes, suggesting a vast network of DDB1-CUL4A E3 ligases.

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