The BECN1 N-terminal domain is intrinsically disordered
Erinna F Lee1,2,3,4,5, Matthew A Perugini6, Anne Pettikiriarachchi1
1a The Walter and Eliza Hall Institute of Medical Research , Parkville , Victoria , Australia.
Autophagy
|April 6, 2016
Summary
The N-terminal domain of Beclin 1 (BECN1) is intrinsically disordered. It remains disordered upon binding BCL2L1, except for the BH3 subdomain, revealing key structural insights into autophagy regulation.
Area of Science:
- Molecular Biology
- Structural Biology
- Cell Biology
Background:
- Beclin 1 (BECN1) is crucial for initiating autophagosome formation.
- Previous structural studies focused on BECN1's central and C-terminal domains.
- The N-terminal domain of BECN1 remained structurally uncharacterized due to production challenges.
Purpose of the Study:
- To express and purify the N-terminal domain of BECN1 (residues 1-150).
- To perform detailed biophysical characterization, including NMR spectroscopy.
- To elucidate the structural behavior of the BECN1 N-terminal domain and its interaction with BCL2L1.
Main Methods:
- Protein expression and purification of BECN1 N-terminal domain (residues 1-150).
- Nuclear Magnetic Resonance (NMR) spectroscopy for biophysical characterization.
- Analysis of BECN1 N-terminal domain interaction with BCL2L1 and competitive inhibitors.
Main Results:
- The BECN1 N-terminal domain (residues 1-150) was successfully expressed and purified.
- NMR studies revealed the BECN1 N-terminal domain is intrinsically disordered.
- Upon binding BCL2L1, the BECN1 N-terminal domain remains disordered, except for the BH3 subdomain, which forms an alpha-helix that reverts to disorder upon inhibitor-induced dissociation.
Conclusions:
- The N-terminal domain of BECN1 is predominantly intrinsically disordered.
- Binding to BCL2L1 induces a transient helical structure in the BH3 subdomain.
- No significant interactions were observed between the N- and C-terminal domains of BECN1.
Keywords:
BCL2BECN1BH3 domainBeclin 1autophagyintrinsically disordered protein; nuclear magnetic resonanceMore Related Videos
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