Structure of a Membrane Tethering Complex Incorporating Multiple SNAREs
Kevin A DAmico1, Abigail E Stanton1, Jaden D Shirkey1
1Department of Molecular Biology, Princeton University, Princeton, NJ 08544.
Biorxiv : the Preprint Server for Biology
|February 13, 2023
Summary
The Dsl1 complex, a membrane tethering complex, binds to SNAREs and reveals common principles of MTC function, suggesting tethers and SNAREs work as one machine.
Area of Science:
- Cellular biology
- Structural biology
Background:
- Membrane fusion in eukaryotic cells relies on membrane tethering complexes (MTCs) and SNARE proteins.
- MTCs initiate membrane attachment, while SNAREs bridge membranes for fusion.
Approach:
- Cryo-electron microscopy (cryo-EM) was used to determine the structure of the Dsl1 complex bound to endoplasmic reticulum-anchoring SNAREs.
- Comparative analysis with the exocyst MTC was performed.
Key Points:
- The 255-kDa Dsl1 complex structure reveals SNARE N-terminal domains integral to the complex.
- The Dsl1 complex configuration shows unexpected similarities to the 850-kDa exocyst MTC.
- This suggests conserved mechanisms for MTC function.
Conclusions:
- Common principles of MTC function are likely shared across different complexes.
- Tethers and SNAREs may function collaboratively as an integrated machine in membrane fusion.
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