GO:0008307 structural constituent of muscle: Mechanism, Genes and Research Methods
Research-grade guide for scientists and biopharma professionals
Key Takeaways
• GO:0008307 (structural constituent of muscle) is a molecular function describing proteins that contribute to the structural integrity of a muscle fiber [1,2].
• Key proteins include myosin heavy chains (MYH1, MYH2, MYH7), actin (ACTA1), titin (TTN), desmin (DES), and myosin-binding protein H (MYBPH).
• These proteins form sarcomeres and the extrasarcomeric cytoskeleton, enabling force generation and transmission [1,2].
• Mutations in genes encoding structural muscle proteins cause laminopathies, cardiomyopathies, and muscular dystrophies.
• The extracellular matrix niche and myofascial chains are critical for muscle structural integrity and force transmission [1,2,5].
• Research methods include CRISPR knockout/knock-in models, proteomics, and imaging to study structural roles [4,8].
Description
The Gene Ontology (GO) term GO:0008307, structural constituent of muscle, defines the molecular function of proteins that contribute to the structural integrity of a muscle fiber. This function is essential for muscle contraction, force transmission, and maintenance of muscle architecture. Proteins annotated with this term include major sarcomeric components such as myosin, actin, titin, and desmin, as well as accessory proteins like myosin-binding protein H. Understanding this term is crucial for researchers studying muscle development, function, and disease. The structural integrity of muscle fibers relies on a complex network of proteins that form sarcomeres and link them to the extracellular matrix [2,5]. Disruptions in these proteins lead to a range of myopathies and cardiomyopathies, making this GO term a focal point for both basic and translational research. This article synthesizes authoritative QuickGO data and verified PubMed literature to provide a comprehensive overview of GO:0008307, its associated genes, mechanisms, and research methodologies.
structural constituent of muscle At A Glance
| GO ID | GO:0008307 |
|---|---|
| GO term | structural constituent of muscle |
| Ontology | molecular_function |
| Synonym | none |
| Major function | Contributes to the structural integrity of a muscle fiber |
| Related cellular component | Sarcomere, cytoskeleton, extracellular matrix |
| Related biological process | Muscle contraction, myofibril assembly |
| Key genes | MYH1, MYH2, MYH7, ACTA1, TTN, DES, MYBPH, COL1A1 |
What Is GO:0008307?
GO:0008307 (structural constituent of muscle) is a molecular function term describing the action of a molecule that contributes to the structural integrity of a muscle fiber. This includes proteins that form the contractile apparatus, cytoskeletal networks, and anchoring structures within muscle cells, enabling them to withstand mechanical stress and transmit force.
Why Is structural constituent of muscle Important in Cell Biology?
The structural constituent of muscle function is fundamental to muscle physiology, as it ensures the mechanical stability and contractile efficiency of muscle fibers. Proteins with this function are critical for force generation, transmission, and maintenance of muscle architecture [1,2]. Dysregulation or mutation of these proteins leads to severe diseases, including muscular dystrophies, cardiomyopathies, and laminopathies. Moreover, the extracellular matrix niche and myofascial chains influence muscle stem cell behavior and force transmission, highlighting the broader importance of structural integrity [1,2,5]. Research into this GO term aids in understanding muscle development, regeneration, and disease pathogenesis, and informs therapeutic strategies.
• Mutations in structural muscle proteins cause congenital myopathies and cardiomyopathies.
• Structural integrity is essential for effective force transmission along myofascial chains [1,2].
• The extracellular matrix niche regulates muscle stem cell function and regeneration.
• Myosin-binding protein H modulates sarcomere structure and function.
• Airway smooth muscle structural malleability affects respiratory function.
• Diabetes alters the macromolecular phenotype of skeletal muscle.
• Cachexia-related muscle fibrosis involves Runx2/COL1A1 axis and structural remodeling.
• CRISPR models enable precise study of structural gene functions.
• Proteomics and imaging reveal structural protein interactions.
• Targeting structural proteins offers therapeutic potential for muscle disorders.
What Happens During structural constituent of muscle?
Sarcomere Assembly and Organization
In simple terms: Muscle proteins build a repeating unit called the sarcomere, which is the basic contractile unit of muscle.
The sarcomere is composed of thick filaments (myosin) and thin filaments (actin), along with titin and other accessory proteins. Myosin-binding protein H (MYBPH) is a component of the thick filament that contributes to sarcomere structure and function. The precise arrangement of these proteins ensures efficient force generation and transmission.
Cytoskeletal Linkage and Force Transmission
In simple terms: Proteins connect the sarcomere to the cell membrane and extracellular matrix to transmit force.
Desmin, a muscle-specific intermediate filament, links sarcomeres to the sarcolemma and extracellular matrix, maintaining structural integrity. Myofascial chains provide a continuous network for force transmission across muscles [1,2]. Disruption of these linkages leads to muscle weakness and disease.
Extracellular Matrix Niche Interactions
In simple terms: The environment around muscle cells, called the extracellular matrix, supports muscle stem cells and structural stability.
The extracellular matrix niche of muscle stem cells provides biochemical and mechanical signals that regulate stem cell quiescence and activation. Collagen and other matrix proteins contribute to the structural integrity of muscle fibers and influence regeneration [4,5].
Structural Malleability in Smooth Muscle
In simple terms: Smooth muscle can change its structure in response to demands, affecting organ function.
Airway smooth muscle exhibits structural malleability that influences its contractile properties and airway responsiveness. This plasticity involves reorganization of cytoskeletal and contractile proteins, highlighting the dynamic nature of structural constituents.
Key Genes Involved in GO:0008307 structural constituent of muscle
The following genes encode proteins that function as structural constituents of muscle, each with distinct roles and research relevance.
| Gene | Major Role | Research Relevance |
|---|---|---|
| MYH1 | Myosin heavy chain 1, fast-twitch skeletal muscle | Muscle fiber type specification, contractile properties |
| MYH2 | Myosin heavy chain 2, fast-twitch skeletal muscle | Muscle atrophy, fiber type switching |
| MYH7 | Myosin heavy chain 7, slow-twitch and cardiac muscle | Cardiomyopathy, hypertrophic cardiomyopathy |
| ACTA1 | Alpha-actin, thin filament component | Nemaline myopathy, actin myopathy |
| TTN | Titin, elastic filament and sarcomere organizer | Dilated cardiomyopathy, muscular dystrophy |
| DES | Desmin, intermediate filament linking sarcomeres | Desmin-related myopathy, cardiomyopathy |
| MYBPH | Myosin-binding protein H, thick filament regulator | Sarcomere assembly, cardiac function |
| COL1A1 | Collagen type I, extracellular matrix component | Muscle fibrosis, cachexia |
| LMNA | Lamin A/C, nuclear envelope protein | Striated muscle laminopathies |
| RUNX2 | Transcription factor regulating collagen | Muscle fibrosis, cachexia |
| DTX3L | E3 ubiquitin ligase, regulates Runx2/COL1A1 | Cachexia-related fibrosis |
| MYOD1 | Myogenic transcription factor | Muscle differentiation, regeneration |
| MYOG | Myogenin, myogenic transcription factor | Muscle differentiation |
| PAX7 | Paired box 7, satellite cell marker | Muscle stem cell maintenance |
| FLNC | Filamin C, actin-crosslinking protein | Myofibrillar myopathy, cardiomyopathy |
| BAG3 | Co-chaperone, sarcomere maintenance | Myofibrillar myopathy, cardiomyopathy |
| CRYAB | Alpha-B crystallin, chaperone | Myofibrillar myopathy, desmin-related myopathy |
How Is structural constituent of muscle Regulated?
The expression and function of structural muscle proteins are regulated at multiple levels. Transcriptional regulation by myogenic regulatory factors (e.g., MYOD1, MYOG) controls muscle-specific gene expression. Post-translational modifications, such as phosphorylation and ubiquitination, modulate protein stability and interactions. For example, the E3 ubiquitin ligase DTX3L negatively regulates the Runx2/COL1A1 axis, affecting collagen deposition and muscle fibrosis in cachexia. Additionally, the extracellular matrix niche provides mechanical and biochemical cues that regulate muscle stem cell activity and structural remodeling.
structural constituent of muscle and Human Disease
| Gene | Disease / Biology | Potential Experimental Model |
|---|---|---|
| LMNA | Striated muscle laminopathies | Knock-in mouse model of LMNA mutation |
| COL1A1 | Cachexia-related muscle fibrosis | Knockout or overexpression in muscle cells |
| DES | Desmin-related myopathy | Des knockout mouse |
| MYH7 | Hypertrophic cardiomyopathy | Knock-in mouse model of MYH7 mutation |
| TTN | Dilated cardiomyopathy | CRISPR knockout in iPSC-derived cardiomyocytes |
Striated Muscle Laminopathies
Mutations in LMNA, encoding lamin A/C, cause striated muscle laminopathies, including Emery-Dreifuss muscular dystrophy and dilated cardiomyopathy. These diseases involve disruption of nuclear envelope structure and mechanotransduction, leading to muscle weakness and cardiac dysfunction.
Cachexia-Related Muscle Fibrosis
Cachexia is associated with excessive collagen deposition and muscle fibrosis. The Runx2/COL1A1 axis promotes fibrosis, and its inhibition by DTX3L or L-carnitine reduces fibrosis and improves muscle structure.
Myofibrillar Myopathies
Mutations in DES, FLNC, BAG3, and CRYAB cause myofibrillar myopathies characterized by disruption of sarcomeric and cytoskeletal structures, leading to muscle weakness and cardiomyopathy.
Diabetes-Induced Muscle Changes
Diabetes alters the macromolecular phenotype of skeletal muscle, affecting structural proteins and contributing to muscle dysfunction. Infrared spectroscopy reveals changes in protein composition and structure.
From structural constituent of muscle-Related Genes to Experimental Models
| Research Question | Suitable Model |
|---|---|
| Does gene X contribute to sarcomere assembly? | Knockout in C2C12 myoblasts |
| Does mutation Y affect force transmission? | Point mutation knock-in in mouse muscle |
| Does overexpression of gene Z cause hypertrophy? | Overexpression in transgenic mouse |
| Does tagged protein localize to sarcomere? | Tagged knock-in in iPSC-derived cardiomyocytes |
| Does gene X regulate muscle stem cell quiescence? | Conditional knockout in satellite cells |
| Does gene X affect extracellular matrix remodeling? | Knockout in muscle fibroblasts |
How to Study the structural constituent of muscle Process
| Method | What It Measures | Typical Application |
|---|---|---|
| CRISPR knockout | Loss of gene function | Determine necessity of structural protein |
| Point mutation knock-in | Effect of specific mutation | Model human myopathy mutations |
| Overexpression | Gain of function | Study hypertrophy or fibrosis |
| Proteomics | Protein composition and modifications | Identify disease biomarkers |
| Infrared spectroscopy | Macromolecular phenotype | Assess muscle structural changes |
| Immunofluorescence | Protein localization | Visualize sarcomere structure |
| Force spectroscopy | Mechanical properties | Measure muscle fiber stiffness |
CRISPR-Based Genetic Models
CRISPR/Cas9 enables precise knockout, point mutation, knock-in, and overexpression of genes encoding structural muscle proteins. These models help determine causal roles in muscle development and disease.
Proteomics and Structural Analysis
Mass spectrometry and infrared spectroscopy reveal the macromolecular composition and structural changes in muscle tissue, identifying alterations in structural proteins under disease conditions.
Imaging and Force Measurements
Fluorescence microscopy and atomic force microscopy visualize sarcomere organization and measure mechanical properties of muscle fibers, linking structural integrity to function [1,2].
Transcriptomics and Bioinformatics
RNA-seq and bioinformatics analyses identify expression changes in structural genes and regulatory networks, providing insights into muscle adaptation and disease [4,5].
How CRISPR Can Be Used to Study GO:0008307 structural constituent of muscle
Knockout
CRISPR knockout of structural muscle genes (e.g., DES, MYH7) in cell and animal models reveals their essential roles in sarcomere assembly and muscle function. For example, Des knockout mice develop cardiomyopathy and skeletal myopathy.
Point Mutation
Introducing disease-associated point mutations (e.g., in LMNA or MYH7) via CRISPR knock-in recapitulates human phenotypes, enabling study of molecular mechanisms and drug testing [3,6].
Knock-in
Tagged knock-in of structural proteins (e.g., MYBPH-GFP) allows live-cell imaging of sarcomere dynamics and protein turnover.
Overexpression
CRISPR activation or transgenic overexpression of structural genes (e.g., COL1A1) models fibrosis and hypertrophy, providing insights into pathological remodeling.
How EDITGENE Supports structural constituent of muscle Research
Researchers studying structural constituent of muscle-related genes often need to determine whether a candidate gene is causally involved in muscle structure and disease. EDITGENE provides comprehensive CRISPR services to accelerate this research.
Contact EDITGENE today to design your custom CRISPR model for structural constituent of muscle research.
Frequently Asked Questions About structural constituent of muscle
What is GO:0008307?
GO:0008307 is the Gene Ontology molecular function term for structural constituent of muscle, describing proteins that contribute to the structural integrity of a muscle fiber.
What genes are involved in structural constituent of muscle?
Key genes include MYH1, MYH2, MYH7, ACTA1, TTN, DES, MYBPH, COL1A1, and LMNA, among others [3,6].
What diseases are associated with structural constituent of muscle?
Mutations in these genes cause striated muscle laminopathies, cardiomyopathies, muscular dystrophies, and cachexia-related fibrosis [3,4].
How can I study structural constituent of muscle genes?
CRISPR knockout, point mutation, knock-in, and overexpression models, combined with proteomics and imaging, are standard approaches [4,8].
What is the role of myosin-binding protein H?
Myosin-binding protein H (MYBPH) is a thick filament component that regulates sarcomere structure and function.
How does the extracellular matrix affect muscle structure?
The extracellular matrix niche provides mechanical support and signals that regulate muscle stem cells and structural integrity.
What is the role of desmin in muscle?
Desmin is an intermediate filament protein that links sarcomeres to the cell membrane, maintaining structural integrity.
Can CRISPR be used to model muscle diseases?
Yes, CRISPR knockout and knock-in models recapitulate human myopathies and cardiomyopathies [3,6].
What is cachexia-related muscle fibrosis?
Cachexia involves excessive collagen deposition and fibrosis, regulated by the Runx2/COL1A1 axis.
How does diabetes affect muscle structure?
Diabetes alters the macromolecular phenotype of skeletal muscle, affecting structural proteins.
Conclusion
GO:0008307 (structural constituent of muscle) is a fundamental molecular function that underpins muscle integrity and function. The proteins annotated with this term, including myosin, actin, titin, desmin, and MYBPH, are critical for sarcomere assembly, force transmission, and extracellular matrix interactions [1,2,6]. Disruption of these proteins leads to a spectrum of muscle diseases, from laminopathies to cardiomyopathies. Advances in CRISPR-based models and high-throughput methods are accelerating our understanding of these structural components and their roles in health and disease [4,8]. Targeting structural constituents of muscle holds promise for therapeutic interventions in muscle disorders.
References
- 1. Wilke J et al.. 2016. What Is Evidence-Based About Myofascial Chains: A Systematic Review.. Arch Phys Med Rehabil 97(3):454-61 PMID: 26281953
- 2. Krause F et al.. 2016. Intermuscular force transmission along myofascial chains: a systematic review.. J Anat 228(6):910-8 PMID: 27001027
- 3. Azibani F et al.. 2014. Striated muscle laminopathies.. Semin Cell Dev Biol 29:107-15 PMID: 24440603
- 4. Lu Z et al.. 2024. l-Carnitine relieves cachexia-related skeletal muscle fibrosis by inducing deltex E3 ubiquitin ligase 3L to negatively regulate the Runx2/COL1A1 axis.. J Cachexia Sarcopenia Muscle 15(5):1953-1964 PMID: 39091264
- 5. Chrysostomou E et al.. 2024. The extracellular matrix niche of muscle stem cells.. Curr Top Dev Biol 158:123-150 PMID: 38670702
- 6. Barefield DY. 2024. Myosin-binding protein-H: Not just filler.. J Gen Physiol 156(12) PMID: 39485243
- 7. Seow CY et al.. 2011. Emergence of airway smooth muscle functions related to structural malleability.. J Appl Physiol (1985) 110(4):1130-5 PMID: 21127211
- 8. Zupančič B et al.. 2023. Exploration of macromolecular phenotype of human skeletal muscle in diabetes using infrared spectroscopy.. Front Endocrinol (Lausanne) 14:1308373 PMID: 38189046
