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Updated: Jul 9, 2026
09:05
Cycloheximide Chase Analysis of Protein Degradation in Saccharomyces cerevisiae
Published on: April 18, 2016
OPTN (optineurin)-mediated selective substrate recognition in Golgi membrane-associated degradation
Yoichi Nibe-Shirakihara1, Shigeomi Shimizu1
1Department of Pathological Cell Biology, Advanced Research Initiative, Institute of Integrated Research, Institute of Science Tokyo, Chiyoda-ku, Tokyo Japan.
Autophagy
|July 8, 2026
Summary
Golgi membrane-associated degradation (GOMED) uses optineurin (OPTN) to recognize and degrade specific proteins within the Golgi. This pathway is crucial for clearing mitochondria during red blood cell development.
Area of Science:
- Cell Biology
- Molecular Biology
- Protein Degradation Pathways
Background:
- Golgi membrane-associated degradation (GOMED) is a protein degradation pathway affecting proteins in the trans-Golgi cisternae.
- GOMED shares morphological similarities with macroautophagy/autophagy, but its substrate recognition mechanism is not well understood.
Purpose of the Study:
- To elucidate the substrate recognition mechanism of GOMED.
- To identify the receptor protein responsible for selective cargo recognition in GOMED.
Main Methods:
- Identification of key proteins involved in GOMED.
- Analysis of protein-ubiquitination linkage types.
- In vivo studies using mouse models.
Main Results:
- Optineurin (OPTN) was identified as an essential receptor protein for GOMED.
- OPTN binds to K33-linked polyubiquitinated proteins processed through the Golgi.
- OPTN delivers these proteins to GOMED structures for degradation.
- OPTN-dependent GOMED is vital for mitochondrial clearance during erythrocyte maturation.
- Optn-deficient mice exhibit erythrocytes that retain mitochondria.
Conclusions:
- The study defines the molecular basis of selective cargo recognition in GOMED.
- OPTN acts as the receptor mediating the selective degradation of specific Golgi-trafficked proteins.
- OPTN-dependent GOMED plays a critical role in cellular quality control, exemplified by mitochondrial clearance in erythropoiesis.
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