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BAG6/BAT3: emerging roles in quality control for nascent polypeptides
Hiroyuki Kawahara1, Ryosuke Minami, Naoto Yokota
1Department of Biological Sciences, Laboratory of Cell Biology and Biochemistry, Tokyo Metropolitan University, Tokyo, Japan. hkawa@tmu.ac.jp
Journal of Biochemistry
|January 1, 2013
Summary
BAG6 (also known as BAT3/Scythe) is crucial for controlling how new proteins are made, especially those prone to clumping. It ensures proper protein folding, degradation, or insertion into membranes, vital for cell health.
Area of Science:
- Molecular Biology
- Cell Biology
- Protein Quality Control
Background:
- BAG6 (also known as BAT3/Scythe) is a ubiquitin-like protein involved in diverse cellular processes.
- Its role in apoptosis, antigen presentation, and T-cell response is known.
- Recent evidence highlights its function in polypeptide biogenesis quality control.
Purpose of the Study:
- To review the physiological roles of BAG6.
- To emphasize BAG6's function in the quality control of nascent chain polypeptides.
- To connect diverse BAG6 functions to membrane protein biogenesis.
Main Methods:
- Literature review of recent studies on BAG6.
- Analysis of BAG6's role in protein quality control pathways.
- Focus on BAG6's interaction with client proteins, including transmembrane proteins.
Main Results:
- BAG6 is essential for the quality control of aggregation-prone polypeptide biogenesis.
- BAG6 forms a complex that dictates the fate of newly synthesized proteins (membrane insertion, degradation, aggregation).
- Transmembrane proteins are identified as major clients of BAG6, linking its functions to membrane protein biogenesis.
Conclusions:
- BAG6 plays a critical role in managing the biogenesis of membrane proteins.
- Understanding BAG6's function in nascent chain polypeptide quality control provides insight into its diverse roles.
- BAG6-mediated control of membrane protein biogenesis is a unifying concept for its known functions.
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