GO:0030134 COPII-coated ER to Golgi transport vesicle: Components, Assembly and Research Methods
Research-grade guide for scientists and biopharma professionals
Key Takeaways
• GO:0030134 describes COPII-coated vesicles that carry cargo from the rough endoplasmic reticulum (ER) to the Golgi apparatus in anterograde transport.
• The COPII coat is built from the Sec23p/Sec24p and Sec13p/Sec31p heterodimers, which together deform the ER membrane and select cargo.
• COPII vesicle formation is a tightly regulated, multi-step process that includes Sar1 activation, cargo recognition, coat assembly, and membrane scission.
• Defects in COPII components are linked to human disease, including T cell alloimmunity and inherited disorders of secretion.
• Research on COPII vesicles uses live-cell imaging, proteomics, and CRISPR-based genome editing to dissect gene function.
• Understanding COPII vesicle biology provides a framework for studying ER-to-Golgi transport in health and disease.
Description
COPII-coated ER to Golgi transport vesicles are small membrane-bound carriers that move newly synthesized proteins from the endoplasmic reticulum (ER) to the Golgi apparatus. This anterograde transport step is essential for the delivery of secretory and membrane proteins to their correct destinations, and it is conserved from yeast to humans. The COPII coat, composed of the Sec23p/Sec24p and Sec13p/Sec31p heterodimers, assembles on the ER membrane and selects cargo for export. Researchers study these vesicles to understand fundamental cell biology, membrane trafficking, and the molecular basis of diseases caused by transport defects. Because COPII vesicles are central to protein secretion, they are also a focus for therapeutic strategies targeting secretory pathways.
COPII-coated ER to Golgi transport vesicle At A Glance
| GO ID | GO:0030134 |
|---|---|
| GO term | COPII-coated ER to Golgi transport vesicle |
| Ontology | cellular_component |
| Synonym | COPII-associated ER to Golgi transport vesicle; COPII-associated vesicle; COPII-coated vesicle; COPII vesicle; endoplasmic reticulum-Golgi transport vesicle; endoplasmic reticulum to Golgi transport vesicle; ER-Golgi transport vesicle; ER to Golgi constitutive secretory pathway transport vesicle; ER to Golgi transport vesicle |
| Major function | Anterograde transport of proteins from the rough ER to the Golgi apparatus |
| Coat components | Sec23p/Sec24p and Sec13p/Sec31p heterodimers |
| Cellular location | Cytoplasm, associated with the ER membrane and Golgi apparatus |
| Related process | Protein secretion, ER-to-Golgi transport |
What Is GO:0030134?
GO:0030134 is a cellular component term that defines a vesicle coated with the COPII coat complex. The COPII coat is formed by the Sec23p/Sec24p and Sec13p/Sec31p heterodimers, and these vesicles mediate the transport of proteins from the rough ER to the Golgi apparatus in anterograde transport. This term encompasses synonyms such as COPII-associated vesicle, COPII-coated vesicle, and ER-to-Golgi transport vesicle, reflecting its role in the early secretory pathway.
Why Is COPII-coated ER to Golgi transport vesicle Important in Cell Biology?
COPII-coated vesicles are the primary vehicles for moving cargo out of the ER, making them indispensable for protein secretion, membrane homeostasis, and cellular communication. Dysregulation of COPII function has been implicated in immune disorders and other diseases, highlighting their clinical relevance. Studying these vesicles helps researchers understand how cells maintain organelle identity and respond to secretory demand.
• COPII vesicles are essential for the anterograde transport of secretory proteins from the ER to the Golgi.
• They maintain ER homeostasis by removing misfolded or excess proteins.
• COPII components are conserved across eukaryotes, enabling model organism studies.
• Defects in COPII-mediated transport can lead to immune dysfunction and alloimmunity.
• COPII vesicles are targets for understanding viral hijacking of secretory pathways.
• They play a role in the delivery of receptors and signaling molecules to the cell surface.
• Research on COPII vesicles informs biotechnology applications such as recombinant protein production.
• COPII vesicle formation is a model for studying membrane curvature and cargo sorting.
What Happens During COPII-coated ER to Golgi transport vesicle?
Initiation at the ER membrane
In simple terms: The process starts when a small protein called Sar1 is activated at the ER membrane.
COPII vesicle formation begins with the activation of the small GTPase Sar1 by its guanine nucleotide exchange factor Sec12 at the ER membrane. Activated Sar1 inserts into the membrane and recruits the Sec23p/Sec24p heterodimer, which together with Sec13p/Sec31p forms the COPII coat. This initial step is critical for selecting the site of vesicle budding and for cargo recognition.
Cargo selection and coat assembly
In simple terms: The COPII coat grabs specific proteins that need to leave the ER and packages them into a vesicle.
The Sec23p/Sec24p heterodimer recognizes cargo proteins through export signals, while the Sec13p/Sec31p heterodimer polymerizes to form the outer coat and induce membrane curvature. This step ensures that only properly folded and selected cargo is included in the vesicle. The coat also excludes ER-resident proteins, maintaining organelle identity.
Vesicle scission and release
In simple terms: The vesicle pinches off from the ER membrane and is released into the cytoplasm.
After coat assembly, the vesicle undergoes scission from the ER membrane, a process that requires the COPII coat and possibly additional factors. The released COPII vesicle then travels toward the Golgi apparatus. Short-distance vesicle transport may also involve phase separation mechanisms that facilitate efficient movement.
Tethering and fusion at the Golgi
In simple terms: The vesicle finds the Golgi and fuses with it to deliver its cargo.
Upon reaching the Golgi, the COPII vesicle is tethered and fused with the Golgi membrane, delivering its cargo into the Golgi lumen or membrane. This step is mediated by tethering factors and SNARE proteins, ensuring directional transport. Retrograde transport from Golgi to ER is regulated separately, for example by diacylglycerol in yeast.
Key Genes Involved in GO:0030134 COPII-coated ER to Golgi transport vesicle
The following genes encode core components and regulators of COPII-coated ER to Golgi transport vesicles.
| Gene | Major Role | Research Relevance |
|---|---|---|
| SAR1A | Small GTPase that initiates COPII coat assembly | Key regulator of vesicle budding; knockout studies reveal transport defects |
| SAR1B | Small GTPase paralog of SAR1A | Mutations linked to lipid absorption disorders; model for secretion defects |
| SEC23A | Component of the Sec23p/Sec24p heterodimer; cargo selection | Mutations cause cranio-lenticulo-sutural dysplasia; target for CRISPR knockout |
| SEC24A | Cargo receptor in the Sec23p/Sec24p heterodimer | Determines cargo specificity; knockout affects secretion of specific proteins |
| SEC13 | Component of the Sec13p/Sec31p heterodimer; outer coat | Structural role in coat polymerization; studied in membrane curvature |
| SEC31A | Component of the Sec13p/Sec31p heterodimer | Regulates coat assembly and vesicle size; knockout impairs ER export |
| SEC12 | Guanine nucleotide exchange factor for Sar1 | Essential for COPII initiation; overexpression activates transport |
| SEC16A | Scaffold protein that organizes COPII assembly sites | Regulates vesicle budding sites; knockout alters ER exit sites |
| SEC16B | Paralog of SEC16A | Modulates COPII dynamics; studied in secretion efficiency |
| SEC22B | SNARE protein involved in vesicle fusion | Required for Golgi fusion; knockout blocks transport |
| BET1 | SNARE protein | Facilitates vesicle docking; studied in ER-to-Golgi transport |
| GOSR1 | Golgi SNARE protein | Mediates fusion at the Golgi; knockout affects secretion |
| USO1 | Tethering factor | Tethers vesicles to Golgi; knockout impairs transport |
| TRAPPC3 | Component of TRAPP tethering complex | Regulates vesicle tethering; mutations linked to disease |
| RAB1A | Small GTPase regulating vesicle docking | Controls transport; knockout affects Golgi structure |
| RAB1B | Paralog of RAB1A | Modulates ER-to-Golgi trafficking; studied in secretion |
| NLP | ER-to-Golgi transport regulator | Nlp-dependent transport; knockout alters vesicle dynamics |
| KDELR1 | Receptor for ER retrieval | Maintains ER residency; knockout affects retrograde transport |
How Is COPII-coated ER to Golgi transport vesicle Regulated?
COPII vesicle formation is regulated by the small GTPase Sar1, whose activity is controlled by the guanine nucleotide exchange factor Sec12 and GTPase-activating proteins. Phosphorylation and other post-translational modifications of COPII components can modulate coat assembly. Additionally, retrograde transport from Golgi to ER is regulated by diacylglycerol in Saccharomyces cerevisiae, which influences lipid homeostasis and membrane trafficking. Short-distance vesicle transport may also be regulated by phase separation, providing a mechanism for efficient cargo movement.
COPII-coated ER to Golgi transport vesicle and Human Disease
| Gene | Disease / Biology | Potential Experimental Model |
|---|---|---|
| SEC23A | Cranio-lenticulo-sutural dysplasia | Knockout or point-mutation cell models to study secretion defects |
| SAR1B | Chylomicron retention disease | Knock-in of patient mutations in cell lines |
| SEC23 | T cell alloimmunity | Knockout in T cells to assess immune responses |
| SEC31A | Defective ER export | Overexpression and knockout models |
| RAB1A | Golgi organization defects | CRISPR knockout in HeLa cells |
COPII vesicles in immune disorders
SEC23-dependent COPII vesicles regulate T cell alloimmunity, and targeting this pathway can modulate immune responses in transplantation. This suggests that COPII components are potential therapeutic targets for immune-related diseases.
COPII dysfunction in inherited diseases
Mutations in COPII genes such as SEC23A and SAR1B cause inherited disorders of secretion, including cranio-lenticulo-sutural dysplasia and chylomicron retention disease. These conditions highlight the importance of COPII vesicles in human physiology.
COPII vesicles and neurodegeneration
Disrupted ER-to-Golgi transport has been implicated in neurodegenerative diseases, where impaired secretion contributes to protein aggregation and neuronal dysfunction. Studying COPII vesicles may reveal mechanisms of neurodegeneration.
From COPII-coated ER to Golgi transport vesicle-Related Genes to Experimental Models
| Research Question | Suitable Model |
|---|---|
| Does loss of SEC23A impair ER-to-Golgi transport? | SEC23A knockout cell line |
| How do patient mutations in SAR1B affect vesicle formation? | SAR1B point-mutation knock-in |
| Can tagged COPII components be used for live imaging? | Tagged knock-in of SEC13 or SEC31A |
| Does overexpression of SAR1A accelerate secretion? | SAR1A overexpression cell line |
| What is the role of NLP in ER-to-Golgi transport? | NLP knockout or knockdown |
| How does SEC16A regulate ER exit sites? | SEC16A knockout and rescue |
How to Study the COPII-coated ER to Golgi transport vesicle Process
| Method | What It Measures | Typical Application |
|---|---|---|
| Live-cell fluorescence microscopy | Vesicle dynamics and localization | Visualizing COPII vesicles in real time |
| Proteomics | Protein composition of vesicles | Identifying cargo and coat proteins |
| CRISPR knockout screening | Genes required for transport | Discovering regulators of COPII function |
| In vitro budding assay | Vesicle formation efficiency | Biochemical dissection of COPII assembly |
| Immunofluorescence | Co-localization of COPII with cargo | Assessing transport defects |
| Electron microscopy | Ultrastructure of vesicles | Visualizing COPII coat morphology |
| RNA-seq | Transcriptional changes upon transport inhibition | Evaluating cellular responses |
Live-cell imaging of COPII vesicles
Fluorescently tagged COPII components, such as SEC13-GFP, allow real-time visualization of vesicle formation and movement. This method reveals dynamics of ER-to-Golgi transport in living cells.
Proteomic analysis of COPII vesicles
Mass spectrometry-based proteomics can identify cargo and coat proteins enriched in purified COPII vesicles. This approach provides a comprehensive view of vesicle composition.
Genetic screens for transport regulators
CRISPR library screening can identify genes that regulate COPII vesicle formation or function. Such screens uncover novel components of the secretory pathway.
Biochemical assays for vesicle budding
In vitro budding assays using purified ER membranes and cytosol measure the efficiency of COPII vesicle formation. These assays are useful for dissecting molecular requirements.
How CRISPR Can Be Used to Study GO:0030134 COPII-coated ER to Golgi transport vesicle
Knockout
CRISPR knockout of COPII genes such as SEC23A or SAR1A can reveal their essential roles in ER-to-Golgi transport. Knockout cell lines are valuable for studying secretion defects and compensatory mechanisms.
Point Mutation
Introducing patient-specific point mutations in COPII genes, such as SAR1B, allows researchers to model inherited diseases and assess functional consequences. Point-mutation knock-in cell lines provide insights into disease mechanisms.
Knock-in
Tagged knock-in of COPII components, for example SEC13-GFP, enables live-cell imaging and biochemical purification of vesicles. Knock-in models are also used to study cargo sorting.
Overexpression
Overexpression of COPII genes like SAR1A or SEC12 can enhance vesicle formation and secretion, providing a tool to study gain-of-function effects. Overexpression models are useful for biotechnology applications.
How EDITGENE Supports COPII-coated ER to Golgi transport vesicle Research
Researchers studying COPII-coated ER to Golgi transport vesicle-related genes often need to determine whether a candidate gene is causally involved in vesicle formation, cargo transport, or disease. EDITGENE provides comprehensive CRISPR-based services to generate precisely engineered cell models for such investigations.
Contact EDITGENE today to design your custom CRISPR model for COPII-coated ER to Golgi transport vesicle research.
Frequently Asked Questions About COPII-coated ER to Golgi transport vesicle
What is GO:0030134?
GO:0030134 is the Gene Ontology term for COPII-coated ER to Golgi transport vesicle, a cellular component involved in anterograde transport from the ER to the Golgi.
What genes are involved in COPII-coated ER to Golgi transport vesicle?
Key genes include SAR1A, SAR1B, SEC23A, SEC24A, SEC13, SEC31A, SEC12, and SEC16A, which encode coat components and regulators.
What is the function of COPII vesicles?
COPII vesicles transport proteins from the rough ER to the Golgi apparatus, facilitating protein secretion and membrane homeostasis.
How are COPII vesicles formed?
COPII vesicles form through Sar1 activation, cargo selection by Sec23p/Sec24p, coat assembly with Sec13p/Sec31p, and membrane scission.
What diseases are associated with COPII dysfunction?
COPII dysfunction is linked to immune disorders, cranio-lenticulo-sutural dysplasia, and chylomicron retention disease.
How can I study COPII vesicles in the lab?
Common methods include live-cell imaging, proteomics, in vitro budding assays, and CRISPR knockout screens.
What is the role of SEC23 in COPII transport?
SEC23 is part of the Sec23p/Sec24p heterodimer that selects cargo and regulates COPII vesicle formation.
Can CRISPR be used to study COPII genes?
Yes, CRISPR knockout, point mutation, knock-in, and overexpression models are widely used to dissect COPII gene function.
What is the difference between COPII and COPI vesicles?
COPII vesicles mediate anterograde ER-to-Golgi transport, while COPI vesicles are involved in retrograde Golgi-to-ER transport.
How does NLP regulate ER-to-Golgi transport?
NLP-dependent ER-to-Golgi transport involves NLP as a regulator of vesicle dynamics, as shown by knockout studies.
Conclusion
COPII-coated ER to Golgi transport vesicles are fundamental to the secretory pathway, ensuring the efficient delivery of proteins from the ER to the Golgi. Understanding their components, assembly, and regulation provides insights into cellular physiology and disease mechanisms. Continued research using advanced CRISPR models and imaging techniques will further elucidate their roles and therapeutic potential.
References
- 1. Yeerken D et al.. 2024. Nlp-dependent ER-to-Golgi transport.. Int J Biol Sci 20(8):2881-2903 PMID: 38904019
- 2. Qiu H et al.. 2024. Short-distance vesicle transport via phase separation.. Cell 187(9):2175-2193.e21 PMID: 38552623
- 3. McCaughey J et al.. 2019. ER-to-Golgi Transport: A Sizeable Problem.. Trends Cell Biol 29(12):940-953 PMID: 31630879
- 4. Gomez-Navarro N et al.. 2016. COP-coated vesicles.. Curr Biol 26(2):R54-R57 PMID: 26811885
- 5. Yang Y et al.. 2026. Retrograde Golgi-to-ER transport is regulated by diacylglycerol in Saccharomyces cerevisiae.. J Cell Sci 139(7) PMID: 41832619
- 8. Kim S et al.. 2021. ER-to-Golgi transport and SEC23-dependent COPII vesicles regulate T cell alloimmunity.. J Clin Invest 131(2) PMID: 33463537
