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Visualizing Intracellular SNARE Trafficking by Fluorescence Lifetime Imaging Microscopy
Published on: December 29, 2017
Evidence that late-endosomal SNARE multimerization complex is promoted by transmembrane segments.
Laura Mascia1, Dieter Langosch
1Lehrstuhl Chemie der Biopolymere, Technische Universität München, Weihenstephaner Berg 3, 85354 Freising, Germany. lmascia@dfb.unipi.it
Biochimica Et Biophysica Acta
|January 30, 2007
Summary
Transmembrane segments of SNARE proteins are crucial for the supramolecular assembly of late endosomal complexes. These segments influence the formation of dimers and multimeric structures, impacting membrane fusion processes.
Area of Science:
- Cell Biology
- Molecular Biology
- Biochemistry
Background:
- SNARE protein complex assembly is vital for membrane fusion.
- Understanding the role of transmembrane segments in this process is key.
Purpose of the Study:
- To investigate the influence of transmembrane segments on late endosomal SNARE complex formation.
- To elucidate the role of these segments in complex assembly and multimerization.
Main Methods:
- In vitro assembly of full-length recombinant SNARE proteins.
- Utilized mutants with deleted or replaced transmembrane segments.
Main Results:
- Endobrevin, syntaxin 7, syntaxin 8, and vti1b readily formed a complex, existing as dimers and multimers.
- Natural transmembrane segments accelerated the conversion to the dimeric form.
- Transmembrane segments were essential for multimerization.
Conclusions:
- Transmembrane segments play a critical role in the supramolecular assembly of the endosomal SNARE complex.
- These segments regulate both complex formation and higher-order structures.
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