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Unconventional secretion of transmembrane proteins
Heon Yung Gee1, Jiyoon Kim1, Min Goo Lee1
1Department of Pharmacology, Brain Korea21 Project for Medical Sciences, Severance Biomedical Science Institute, Yonsei University College of Medicine, Seoul, 03722, Republic of Korea.
Seminars in Cell & Developmental Biology
|March 28, 2018
Summary
Eukaryotic cells use unconventional protein secretion (UPS) to transport proteins bypassing the Golgi apparatus. This review details UPS pathways for transmembrane proteins, crucial for cellular functions.
Area of Science:
- Cell Biology
- Molecular Biology
- Protein Trafficking
Background:
- Eukaryotic cells employ conventional and unconventional pathways for protein delivery.
- Conventional transport involves the endoplasmic reticulum and Golgi apparatus.
- Unconventional protein secretion (UPS) bypasses the Golgi, especially under stress.
Purpose of the Study:
- To review intracellular trafficking pathways of UPS cargo proteins.
- To focus on transmembrane proteins utilizing UPS.
- To discuss the molecular machinery governing UPS of transmembrane proteins.
Main Methods:
- Literature review of established and emerging UPS pathways.
- Analysis of known transmembrane proteins undergoing UPS (Type IV).
- Synthesis of current understanding of molecular mechanisms.
Main Results:
- UPS pathways are diverse and distinct from conventional routes.
- Integral membrane proteins can utilize UPS to reach the plasma membrane.
- Examples include integrin alpha 1, CFTR, and pendrin.
Conclusions:
- UPS is a significant route for protein transport, particularly for transmembrane proteins.
- The molecular mechanisms underlying UPS are complex and not fully elucidated.
- Further research is needed to define the machinery involved in transmembrane protein UPS.
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