Related Experiment Video

Updated: Jun 27, 2025

In Vitro Analysis of E3 Ubiquitin Ligase Function
06:06

In Vitro Analysis of E3 Ubiquitin Ligase Function

Published on: May 14, 2021

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Structural insights into the functional mechanism of the ubiquitin ligase E6AP

Zhen Wang1, Fengying Fan1,2, Zhihai Li2,3

  • 1State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, 201203, China.

Nature Communications
|April 26, 2024
PubMed

Insights

E3 ubiquitin ligase E6AP

Area of Science:

  • Biochemistry
  • Molecular Biology
  • Structural Biology

Background:

  • E3 ubiquitin ligase E6AP dysfunction is implicated in Angelman syndrome and autism spectrum disorder.
  • High-risk HPV E6 protein hijacks E6AP to ubiquitinate p53, contributing to various cancers, notably cervical cancer.

Purpose of the Study:

  • To elucidate the structural mechanisms underlying E6AP activation and substrate ubiquitination.
  • To investigate the role of the E6AP α1-helix in regulating E6AP's monomer-dimer transition.

Main Methods:

  • X-ray crystallography to determine the structure of E6AP and the E6AP/E6 complex.
  • Mutagenesis analysis to probe the function of the α1-helix.

Main Results:

  • E6AP exists as an inactive monomer, while the E6AP/E6 complex forms an active dimer.
  • Complexation with HPV E6 induces a conformational change in the E6AP α1-helix, promoting dimerization.
  • The dimeric structure facilitates substrate binding and ubiquitin transfer through a swaying motion of protomers.

Conclusions:

  • The E6AP α1-helix undergoes conformational changes that control its transition between inactive monomer and active dimer states.
  • Structural insights into E6AP's activation mechanism provide a basis for understanding its role in disease and developing therapeutic strategies.

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