GO:0106138 Sec61 translocon complex binding: Mechanism, Genes and Research Methods
Research-grade guide for scientists and biopharma professionals
Key Takeaways
• GO:0106138 Sec61 translocon complex binding is a molecular function describing the selective binding of a protein or substrate to the Sec61 translocon complex at the endoplasmic reticulum (ER) membrane.
• The Sec61 complex is the conserved protein-conducting channel that mediates co-translational translocation of secretory and membrane proteins into the ER.
• Binding to Sec61 is not passive: it is a regulated step that can determine whether a nascent chain is translocated, membrane-inserted, or targeted for degradation.
• Structural and biophysical studies show that Sec61-binding proteins and substrates engage distinct surfaces of the channel, including the lateral gate and the plug region.
• Mutations affecting Sec61 complex function cause Sec61 channelopathies, including kidney and liver disease and neurodevelopmental phenotypes.
• CRISPR knockout, point-mutation, knock-in and overexpression models are essential to test whether a candidate Sec61-binding protein is causally involved in ER homeostasis and disease.
Description
GO:0106138 Sec61 translocon complex binding is a molecular function term that describes the binding of a protein, peptide or substrate to the Sec61 translocon complex. The Sec61 complex is the central protein-conducting channel of the endoplasmic reticulum (ER) membrane and is responsible for the co-translational translocation of secretory and membrane proteins. Because nearly one third of the proteome enters the ER through Sec61, proteins that bind this complex are positioned at a critical decision point in protein biogenesis. Researchers study this term to understand how substrates are recognized, how channel gating is controlled, and how defects in these interactions contribute to human disease. The function is experimentally defined by binding assays, structural biology and optical-tweezers measurements that quantify the interaction between the Sec61 complex and its binding partners. In this article we integrate the QuickGO definition of GO:0106138 with verified PubMed literature to provide a research-grade overview of the mechanism, key genes, disease links and CRISPR-based research methods relevant to Sec61 translocon complex binding.
Sec61 translocon complex binding At A Glance
| GO ID | GO:0106138 |
|---|---|
| GO term | Sec61 translocon complex binding |
| Ontology | molecular_function |
| Synonym | None listed in QuickGO |
| Definition | Binding to a Sec61 translocon complex. |
| Major function | Selective interaction with the ER protein-conducting channel Sec61 to control translocation, membrane insertion and channel gating |
| Cellular location | Endoplasmic reticulum membrane, at the ribosome-translocon junction |
| Representative binders | Nascent secretory and membrane polypeptides, TRAP complex subunits, and regulatory proteins that dock on Sec61 |
| Disease relevance | Sec61 channelopathies affecting kidney, liver and neurodevelopment |
| Research methods | Optical tweezers, cryo-EM, ribosome profiling, proteomics and CRISPR models |
What Is GO:0106138?
In our own words, GO:0106138 Sec61 translocon complex binding is the molecular function of selectively and non-covalently interacting with the Sec61 translocon complex, the heterotrimeric protein-conducting channel of the ER membrane. This binding event can involve nascent polypeptide chains, accessory targeting factors, or regulatory proteins that dock onto the Sec61 complex to influence translocation, membrane insertion or channel gating. The term is defined at the level of the physical interaction with the Sec61 complex rather than at the level of a downstream biological outcome, so it is used to annotate proteins and substrates that directly engage the channel.
Why Is Sec61 translocon complex binding Important in Cell Biology?
Sec61 translocon complex binding is important because it controls the first committed step in the biogenesis of secretory and membrane proteins, and because perturbations of this interaction are directly linked to human disease. Proteins that bind the Sec61 complex determine whether a nascent chain is translocated into the ER lumen, inserted into the membrane, or rejected for degradation, making this function a central node in ER homeostasis and proteostasis. Clinically, mutations that alter Sec61 complex function or its interactions cause Sec61 channelopathies with kidney, liver and neurological manifestations. For researchers, GO:0106138 provides a precise annotation target for identifying and validating new regulators of ER protein biogenesis using CRISPR-based models and quantitative binding assays.
• Sec61 translocon complex binding governs the entry of secretory and membrane proteins into the ER, a step required for roughly one third of the proteome.
• It determines substrate fate: translocation, membrane insertion or degradation, through regulated engagement of the channel.
• It is a direct target of small-molecule translocon inhibitors, making it relevant to chemical biology and drug discovery.
• Mutations in Sec61 complex components cause Sec61 channelopathies, including kidney and liver disease and neurodevelopmental phenotypes.
• Binding of regulatory proteins such as WDR45 links ER homeostasis to neuronal survival and neurodegeneration.
• The UFM1 E3 ligase recognizes and releases 60S ribosomes from ER translocons, showing that Sec61 interactions are coupled to ribosome quality control.
• Structural studies of TRAP association with the ribosome-Sec61 complex reveal how accessory factors modulate channel function.
• Optical-tweezers measurements of ppαF binding to Sec61 provide quantitative parameters for the interaction, enabling mechanistic modeling.
• CRISPR knockout and point-mutation models allow causal testing of Sec61-binding proteins in ER stress and disease.
• The term supports annotation of new genes in proteostasis, secretion and ER-associated degradation pathways.
Sec61 translocon complex binding: mechanism, components and regulation
Substrate recognition at the ER membrane
In simple terms: Before a protein can enter the ER, it must be recognized and delivered to the Sec61 channel.
Sec61 translocon complex binding begins with the recognition of a nascent polypeptide or a targeting factor at the ER membrane. Structural analysis of translation and protein biogenesis at the ER membrane shows that the ribosome docks onto the Sec61 complex and positions the nascent chain at the channel entrance. Optical-tweezers experiments using the model substrate ppαF demonstrate that the interaction between the substrate and the Sec61 complex can be measured directly and is sensitive to the conformational state of the channel. This recognition step is therefore a regulated binding event that determines whether the substrate commits to translocation.
Channel gating and translocation
In simple terms: Once bound, the channel opens to let the protein pass through the membrane.
After binding, the Sec61 complex undergoes gating transitions that open the pore and allow the nascent chain to move into the ER lumen or into the lipid bilayer. Cryo-EM and biochemical studies show that the plug region and the lateral gate of Sec61 are central to these transitions, and that accessory factors such as the TRAP complex associate with the ribosome-Sec61 complex to modulate them. Small-molecule inhibitors of the translocon, including CADA derivatives, act by interfering with these gating steps, confirming that binding and gating are mechanistically coupled. A common mechanism of Sec61 translocon inhibition by small molecules has been proposed based on structural and functional data.
Accessory factors and the TRAP complex
In simple terms: Helper proteins bind the channel and fine-tune what gets translocated.
Sec61 translocon complex binding is not limited to substrates; accessory proteins also bind the complex and regulate its activity. Structural insights into TRAP association with the ribosome-Sec61 complex reveal how TRAP engages the channel and influences translocon inhibition by a CADA derivative. In addition, the UFM1 E3 ligase recognizes and releases 60S ribosomes from ER translocons, showing that the translocon interface is a hub for quality-control factors that bind and remodel the complex. These findings place GO:0106138 at the center of a dynamic interaction network rather than a static binding event.
Coupling to ribosome quality control and ER homeostasis
In simple terms: When translation goes wrong, proteins that bind Sec61 help clean up and protect the cell.
Binding to the Sec61 complex is coupled to ribosome quality control and ER homeostasis. The UFM1 E3 ligase recognizes and releases 60S ribosomes from ER translocons, a process that requires engagement of the translocon interface. WDR45 contributes to neurodegeneration through regulation of ER homeostasis and neuronal death, linking ER stress responses to neuronal survival. Together, these studies show that Sec61 translocon complex binding is integrated with cellular stress pathways that monitor and maintain ER function.
Pharmacological and disease relevance of the binding interface
In simple terms: Because so many proteins depend on this channel, drugs and mutations that affect binding can cause disease.
The Sec61 binding interface is a validated target for small molecules and a hotspot for disease-causing mutations. Complexity and specificity of Sec61 channelopathies show that human diseases affecting gating of the Sec61 complex arise from mutations that alter its interactions and regulation. Genetic complexity of autosomal dominant polycystic kidney and liver diseases further illustrates how mutations in ER-associated proteins, including those affecting Sec61-related pathways, contribute to clinically heterogeneous disease. Small-molecule inhibitors that target the translocon provide chemical probes to dissect these binding events and to explore therapeutic strategies.
Key Genes Involved in GO:0106138 Sec61 translocon complex binding
The following genes and proteins are experimentally linked to Sec61 translocon complex binding, either as channel subunits, accessory factors, substrates or regulators.
| Gene | Major Role | Research Relevance |
|---|---|---|
| SEC61A1 | Core subunit of the Sec61 channel | Mutations cause Sec61 channelopathies with kidney, liver and immune phenotypes |
| SEC61B | Core subunit of the Sec61 channel | Contributes to channel assembly and gating; studied in translocon inhibition |
| SEC61G | Core subunit of the Sec61 channel | Part of the heterotrimeric complex; relevant to structural studies of ribosome-Sec61 binding |
| TRAP subunits (e.g., SSR1-SSR4) | Accessory complex that associates with ribosome-Sec61 | Modulates translocon inhibition and substrate selection |
| UFM1 | Ubiquitin-like modifier in ribosome quality control | Required for release of 60S ribosomes from ER translocons |
| UFL1 | UFM1 E3 ligase | Recognizes and releases 60S ribosomes from ER translocons |
| WDR45 | Regulator of ER homeostasis | Links ER homeostasis to neurodegeneration and neuronal death |
| PPαF (model substrate) | Model secretory substrate | Used in optical-tweezers measurements of Sec61 binding |
| RPL and RPS ribosomal proteins | Ribosome components docking at Sec61 | Structural studies of translation at the ER membrane |
| SEC62 | Accessory translocon component | Modulates post-translational translocation and ER homeostasis |
| SEC63 | Accessory translocon component | Cooperates with BiP for translocation and gating |
| HSPA5 (BiP) | ER chaperone | Supports translocation and quality control at the translocon |
| PKD1 | Polycystin-1, ER-associated protein | Genetic complexity of ADPKD and liver disease involving ER pathways |
| PKD2 | Polycystin-2, ER-associated protein | Genetic complexity of ADPKD and liver disease involving ER pathways |
| GANAB | Glucosidase II alpha subunit | ADPKD modifier linked to ER proteostasis |
| DNAJB11 | ER co-chaperone | ADPKD-related gene linked to ER protein handling |
| SEC61A1 variants | Disease-associated channel variants | Modeled with point mutations to study gating defects |
How Is Sec61 translocon complex binding Regulated?
Sec61 translocon complex binding is regulated at multiple levels, including the availability of accessory factors such as the TRAP complex and the UFM1 system, and by ER stress pathways that monitor protein folding. The UFM1 E3 ligase recognizes and releases 60S ribosomes from ER translocons, providing a regulated mechanism to clear stalled translation complexes at the channel. WDR45 contributes to ER homeostasis and neuronal survival, indicating that ER stress and autophagy-related signaling influence translocon-associated functions. Small-molecule inhibitors of the translocon can also modulate binding and gating, demonstrating that the interaction is pharmacologically accessible. Mutations in Sec61 complex components alter gating and regulation, as reviewed in the context of Sec61 channelopathies.
Sec61 translocon complex binding and Human Disease
| Gene | Disease / Biology | Potential Experimental Model |
|---|---|---|
| SEC61A1 | Sec61 channelopathy with kidney, liver and immune features | Knock-in of patient variants in cell lines; KO for loss-of-function |
| WDR45 | Neurodegeneration and ER homeostasis | Neuronal KO and overexpression models; ER stress assays |
| UFM1 / UFL1 | Ribosome quality control and proteostasis | KO and tagged knock-in to monitor 60S release from translocons |
| PKD1 / PKD2 | Autosomal dominant polycystic kidney and liver disease | KO and knock-in models in renal epithelial cells |
| TRAP subunits | Translocon regulation and inhibitor response | KO and overexpression models with CADA derivative treatment |
Sec61 channelopathies and kidney-liver disease
Mutations that affect the Sec61 complex and its interactions cause human diseases known as Sec61 channelopathies, which can present with kidney, liver and immune abnormalities. The genetic complexity of autosomal dominant polycystic kidney and liver diseases further highlights how ER-associated proteins, including those involved in Sec61-related pathways, contribute to clinically heterogeneous disease. These observations make GO:0106138 a relevant annotation for genes implicated in ER proteostasis and cystic disease.
Neurodegeneration and ER homeostasis
WDR45 contributes to neurodegeneration through regulation of ER homeostasis and neuronal death, linking Sec61-associated ER functions to neuronal survival. Because the Sec61 complex is the entry point for secretory and membrane proteins in neurons, perturbations in translocon binding and gating can trigger ER stress and cell death. This connection supports the study of Sec61-binding proteins in neurodegenerative disease models.
Ribosome quality control and proteostasis disorders
The UFM1 E3 ligase recognizes and releases 60S ribosomes from ER translocons, a quality-control mechanism that is essential for proteostasis. Defects in this pathway can lead to accumulation of stalled translation complexes at the ER membrane and to proteotoxic stress. Therefore, genes annotated with Sec61 translocon complex binding are candidates for proteostasis-related disorders.
Cancer and translocon-targeted therapy
Small molecules that inhibit the Sec61 translocon, including CADA derivatives, act by interfering with binding and gating events at the channel. A common mechanism of Sec61 translocon inhibition by small molecules has been proposed, supporting the development of translocon-targeted therapeutics. Because secretory and membrane proteins are critical for tumor growth and immune surveillance, Sec61-binding interfaces are of interest in cancer research.
From Sec61 translocon complex binding-Related Genes to Experimental Models
| Research Question | Suitable Model |
|---|---|
| Is a candidate gene required for Sec61 binding and translocation? | CRISPR knockout cell line with translocation and binding assays |
| Does a disease variant alter channel gating? | Point-mutation knock-in of the variant in a clean genetic background |
| Where and when does the protein bind the Sec61 complex? | Endogenous tagged knock-in for imaging and co-immunoprecipitation |
| Does overexpression of the binder change ER homeostasis? | Doxycycline-inducible overexpression cell model |
| Which accessory factors modulate translocon inhibition? | KO of TRAP subunits combined with small-molecule treatment |
| Does loss of the gene cause ribosome accumulation at the ER? | KO followed by ribosome profiling and proteomics |
How to Study the Sec61 translocon complex binding Process
| Method | What It Measures | Typical Application |
|---|---|---|
| Optical tweezers | Binding strength and kinetics of substrate-Sec61 interaction | Quantifying ppαF binding to the Sec61 complex |
| Cryo-EM | Three-dimensional structure of ribosome-Sec61 complexes | Mapping binding interfaces and TRAP association |
| Ribosome profiling | Positions and density of ribosomes on mRNAs | Detecting translation stalls at the ER translocon |
| Proteomics | Protein composition of ER-associated complexes | Identifying new Sec61-binding proteins |
| Co-immunoprecipitation | Physical interaction between proteins | Validating binding of candidate proteins to Sec61 |
| Fluorescence imaging | Subcellular localization and dynamics | Tracking tagged Sec61 binders in live cells |
| CRISPR knockout | Loss-of-function phenotype | Testing requirement of a gene for Sec61 binding |
| Small-molecule treatment | Pharmacological modulation of translocon function | Testing CADA derivatives and other inhibitors |
Optical tweezers and single-molecule binding assays
Optical-tweezers measurements have been used to characterize the interaction between the Sec61 translocon complex and the model substrate ppαF, providing quantitative parameters for binding and unfolding. These assays are valuable for testing how mutations or inhibitors alter the strength and kinetics of Sec61 translocon complex binding.
Structural biology: cryo-EM and tomography
Cryo-electron microscopy and related structural approaches have visualized translation and protein biogenesis at the ER membrane, revealing how the ribosome, Sec61 complex and accessory factors such as TRAP are organized. Structural insights into TRAP association with the ribosome-Sec61 complex and translocon inhibition by a CADA derivative illustrate how these methods define binding interfaces.
Ribosome profiling and proteomics
Ribosome profiling and proteomics can detect changes in translation and in the composition of ER-associated complexes when Sec61-binding proteins are perturbed. The UFM1 E3 ligase recognizes and releases 60S ribosomes from ER translocons, a process that can be monitored by these approaches. Proteomic analysis of ER membranes is also useful to identify new binders of the Sec61 complex.
CRISPR screens and functional genomics
CRISPR library screening and functional genomics can identify genes that modify Sec61 translocon complex binding and ER homeostasis. Candidate hits can then be validated with knockout, point-mutation and overexpression models to establish causality. This workflow is particularly useful for linking GO:0106138 annotations to disease-relevant phenotypes.
How CRISPR Can Be Used to Study GO:0106138 Sec61 translocon complex binding
Knockout
CRISPR knockout of genes encoding Sec61-binding proteins or accessory factors is used to test whether they are required for translocation, ER homeostasis and cell survival. For example, loss of UFM1 pathway components impairs release of 60S ribosomes from ER translocons, which can be detected by ribosome profiling and proteomics. Knockout of WDR45 alters ER homeostasis and neuronal survival, providing a model for neurodegeneration.
Point Mutation
Point-mutation knock-in is used to model disease-associated variants in Sec61 complex components and to dissect gating defects. By introducing specific patient variants into a clean genetic background, researchers can separate effects on binding from effects on channel assembly. Such models are also useful to test whether small-molecule inhibitors can rescue the mutant phenotype.
Knock-in
Tagged knock-in of endogenous Sec61-binding proteins enables imaging, co-immunoprecipitation and proximity labeling under physiological expression levels. This approach avoids artifacts from overexpression and allows the study of binding dynamics at the ER membrane. Knock-in of reporter tags into accessory factor loci can also reveal when and where they engage the translocon.
Overexpression
Overexpression models are used to test whether increased levels of a Sec61-binding protein alter ER homeostasis, translocation efficiency or stress responses. Inducible overexpression allows dose- and time-controlled experiments that can reveal gain-of-function phenotypes. These models complement knockout studies to establish causality in both directions.
How EDITGENE Supports Sec61 translocon complex binding Research
Researchers studying Sec61 translocon complex binding-related genes often need to determine whether a candidate gene is causally involved in ER protein biogenesis, stress responses or disease, rather than merely correlated with a phenotype. This requires precise genetic models that can isolate the contribution of a single gene or variant to the interaction with the Sec61 complex. EDITGENE provides a full suite of CRISPR-based cell models and screening services designed to support such causal studies, from knockout validation to patient-variant knock-in and functional genomics.
Contact EDITGENE today to design your custom CRISPR model for Sec61 translocon complex binding research.
Frequently Asked Questions About Sec61 translocon complex binding
What is GO:0106138 Sec61 translocon complex binding?
GO:0106138 is a molecular function term describing the binding of a protein or substrate to the Sec61 translocon complex, the ER protein-conducting channel.
What genes are involved in Sec61 translocon complex binding?
Key genes include SEC61A1, SEC61B, SEC61G, TRAP subunits, UFM1, UFL1 and WDR45, among others.
Why is Sec61 translocon complex binding important?
It controls the entry of secretory and membrane proteins into the ER and is linked to Sec61 channelopathies and neurodegeneration.
What diseases are associated with Sec61 translocon complex binding?
Sec61 channelopathies, autosomal dominant polycystic kidney and liver diseases, and neurodegeneration have been linked to this function.
How is Sec61 translocon complex binding studied?
Common methods include optical tweezers, cryo-EM, ribosome profiling, proteomics and CRISPR-based models.
What is the Sec61 complex?
The Sec61 complex is the heterotrimeric protein-conducting channel of the ER membrane that mediates co-translational translocation.
Can small molecules inhibit Sec61 translocon binding?
Yes, small molecules such as CADA derivatives inhibit the translocon by interfering with binding and gating events.
How does UFM1 relate to Sec61 translocon complex binding?
The UFM1 E3 ligase recognizes and releases 60S ribosomes from ER translocons, linking quality control to the translocon interface.
What CRISPR models are used for Sec61 research?
Knockout, point-mutation knock-in, tagged knock-in and overexpression models are used to test causality and mechanism.
How can EDITGENE help with Sec61 translocon complex binding research?
EDITGENE provides knockout, point-mutation, knock-in, overexpression, library screening and bioinformatics services tailored to Sec61-related studies.
Conclusion
GO:0106138 Sec61 translocon complex binding captures a central molecular function at the ER membrane, where substrates and regulatory proteins engage the Sec61 channel to control protein biogenesis and ER homeostasis. Verified literature links this function to Sec61 channelopathies, kidney and liver disease, neurodegeneration and proteostasis disorders, and to pharmacological inhibition by small molecules. CRISPR-based knockout, point-mutation, knock-in and overexpression models, combined with structural, biophysical and functional genomics methods, provide the tools needed to move from correlation to causality in this field. Researchers can leverage these approaches, and EDITGENE services, to dissect how individual genes and variants contribute to Sec61 translocon complex binding and its disease-relevant outcomes.
References
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