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Published on: March 16, 2022
Sec12 binds to Sec16 at transitional ER sites.
Elisabeth A Montegna1, Madhura Bhave, Yang Liu
1Department of Molecular Genetics and Cell Biology, The University of Chicago, Chicago, Illinois, United States of America.
Plos One
|February 21, 2012
Summary
The Sec12 protein
Area of Science:
- Cell Biology
- Molecular Biology
- Biochemistry
Background:
- COPII vesicles mediate protein transport from the endoplasmic reticulum (ER).
- Transitional ER (tER) is the specific ER domain for COPII vesicle budding.
- Sec12 initiates COPII coat assembly and is localized to tER sites.
Purpose of the Study:
- To identify the binding partner responsible for the tER localization of Sec12.
- To elucidate the molecular mechanism of Sec12 localization to tER sites.
- To investigate the conserved role of Sec12-Sec16 interaction in ER export.
Main Methods:
- Genetic manipulation in Pichia pastoris and Saccharomyces cerevisiae.
- Overexpression studies of Sec12 and Sec16.
- Deletion analysis of Sec16 C-terminal fragment.
- Biochemical binding assays.
Main Results:
- Sec16 was identified as the saturable binding partner for Sec12.
- Sec16 recruits Sec12 to tER sites, a function dependent on Sec16's C-terminal fragment.
- The C-terminal fragment of Sec16 directly binds to the cytosolic domain of Sec12.
- Human Sec12 also localizes to tER sites, likely via interaction with Sec16A.
Conclusions:
- The interaction between Sec12 and Sec16 is crucial for concentrating Sec12 at tER sites.
- This Sec12-Sec16 interaction plays a conserved role in initiating ER export.
- Understanding this interaction provides insights into the regulation of vesicle formation.
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