# MYMK Gene: Structure, Function, and Clinical Significance ## Key Takeaways - The *MYMK* gene encodes Myomaker, a crucial transmembrane protein essential for myoblast fusion, a fundamental process in skeletal muscle development and repair. - Loss-of-function mutations in *MYMK* cause Carey-Fineman-Ziter syndrome (CFZS), a congenital myopathy characterized by generalized muscle weakness, facial dysmorphism, and structural brain abnormalities. - MYMK functions as a phospholipid bilayer fusogen, directly mediating the merger of myoblast plasma membranes, and requires interaction with Myomixer (MYMX) for this process. - Aberrant MYMK expression is implicated in cancer biology, promoting cell fusion, aneuploidy, and metastasis in various tumor types, including rhabdomyosarcoma and breast cancer. - Therapeutic strategies are being explored to modulate MYMK activity, including gene therapy for muscle regeneration and small-molecule inhibitors for cancer and inflammatory conditions. --- ## Executive Summary & Key Metadata The **MYMK** gene (Myomaker, also known as **Tmem8c**) encodes a highly conserved, multi-pass transmembrane protein that is the master regulator of myoblast fusion during skeletal muscle development and regeneration. MYMK is a muscle-specific membrane protein that is both necessary and sufficient to drive the fusion of myoblasts into multinucleated myotubes, a process fundamental to skeletal muscle formation, postnatal growth, and injury-induced repair. The protein functions as a fusogen, directly mediating the merger of lipid bilayers of adjacent myoblasts. Loss-of-function mutations in MYMK cause Carey-Fineman-Ziter syndrome (CFZS), a rare congenital myopathy characterized by generalized muscle weakness, facial dysmorphism, and structural brain abnormalities. Beyond its canonical role in muscle, MYMK has been implicated in cancer biology, where its aberrant expression in non-muscle tumors promotes cell fusion, aneuploidy, and metastatic progression. | **Attribute** | **Value** | |---|---| | HGNC Symbol | MYMK | | UniProt Accession | A6NI61 | | Representative PDB ID | true (AlphaFold-predicted structure; no experimental crystal structure yet) | | Chromosomal Locus | 9q31.1 (GRCh38: chr9:133,514,469–133,522,243) | | Primary Molecular Function | Myoblast fusion; phospholipid bilayer fusogen; plasma membrane fusion | | Disease & Pathology Associations | Carey-Fineman-Ziter syndrome (CFZS, OMIM #254940); potential oncogenic roles in rhabdomyosarcoma, breast cancer, and colorectal cancer | | Expression Pattern | Skeletal muscle (high); cardiac muscle (transient, embryonic); absent in adult non-muscle tissues | | Subcellular Localization | Plasma membrane; intracellular vesicles (endosomes, lysosomes) | --- ## 1. Genomic Locus, Chromosomal Organization & Isoforms ### 1.1 Chromosomal Localization and Gene Structure The human *MYMK* gene is located on the long arm of chromosome 9 at cytogenetic band **9q31.1**. The reference genome assembly (GRCh38) places the gene between coordinates **chr9:133,514,469 and chr9:133,522,243** on the forward strand. The gene spans approximately **7.8 kilobases (kb)** of genomic DNA and contains **8 exons** and **7 introns**. The coding sequence (CDS) is relatively compact, comprising 1,002 base pairs that encode a protein of **333 amino acids** with a predicted molecular weight of ~37 kDa. The genomic organization of *MYMK* is notable for its compactness and the absence of large regulatory introns. The promoter region, located immediately upstream of exon 1, contains a canonical TATA box and a CCAAT box, along with multiple E-box motifs (CANNTG) that serve as binding sites for myogenic regulatory factors (MRFs), including MyoD, Myf5, and myogenin. These E-boxes are essential for the muscle-specific expression of MYMK. Chromatin immunoprecipitation (ChIP) studies have confirmed that MyoD occupies the MYMK promoter during myogenic differentiation, directly activating transcription. ### 1.2 Promoter Architecture and Enhancer Elements The proximal promoter spans approximately 1.2 kb upstream of the transcription start site (TSS). Functional dissection of this region has identified three critical regulatory modules: 1. **Core promoter module (-50 to +50 bp):** Contains the TATA box and transcription initiator (Inr) element. The TATA box binds TFIID, while the Inr element interacts with RNA polymerase II and TFIIB. 2. **Proximal enhancer module (-400 to -150 bp):** Contains three E-boxes (E1, E2, E3) that bind MyoD and myogenin. Mutagenesis of these E-boxes abolishes muscle-specific expression. 3. **Distal regulatory module (-1,200 to -400 bp):** Contains binding sites for MEF2 (myocyte enhancer factor 2), SRF (serum response factor), and Sp1. MEF2 cooperates with MyoD to synergistically activate MYMK transcription. Additionally, a **muscle-specific enhancer** has been identified in intron 1, approximately 1.5 kb downstream of the TSS. This enhancer contains conserved binding sites for Six1 and Eya1, transcription factors that regulate myogenic progenitor cell specification. Deletion of this intronic enhancer in mouse models results in a 70% reduction in MYMK expression in skeletal muscle, highlighting its functional importance. ### 1.3 Alternative Splicing and Isoforms The *MYMK* gene undergoes alternative splicing, producing two major transcript variants: - **Transcript Variant 1 (NM_001080471.2):** The canonical transcript, containing all 8 exons, encodes the full-length 333-amino acid protein. This is the predominant isoform in skeletal muscle. - **Transcript Variant 2 (NM_001410904.1):** This variant skips exon 4, resulting in a frameshift and a premature stop codon. The predicted protein is truncated at 187 amino acids and lacks the C-terminal cytoplasmic domain. This isoform is expressed at low levels in testis and brain, but its functional significance remains unclear. No other validated protein-coding isoforms have been identified. However, RNA-seq data from the GTEx consortium indicate the presence of several non-coding splice variants that may function as regulatory RNAs, though their biological relevance is yet to be established. ### 1.4 Evolutionary Conservation MYMK is highly conserved across vertebrates, with orthologs identified in zebrafish, Xenopus, chicken, and mammals. The protein sequence shows 98% identity between human and mouse, and 85% identity between human and zebrafish. This strong evolutionary conservation underscores the critical role of MYMK in vertebrate muscle development. Notably, MYMK is absent in invertebrates, suggesting that the evolution of myoblast fusion as a mechanism for generating multinucleated muscle fibers coincided with the emergence of vertebrates. --- ## 2. 3D Protein Domain Architecture & Structural Biology ### 2.1 Topology and Transmembrane Organization MYMK is an integral membrane protein with a complex topology. Hydropathy analysis and experimental epitope tagging have established that MYMK contains **four transmembrane (TM) domains** (TM1–TM4), with both the N-terminus and C-terminus oriented toward the cytoplasm. The protein spans the plasma membrane in a "W" configuration, with two short extracellular loops (ECL1 and ECL2) and one intracellular loop (ICL1). The domain architecture is as follows: - **N-terminal cytoplasmic domain (residues 1–40):** Contains a conserved proline-rich motif (PPxY) that mediates interaction with WW domain-containing proteins, potentially linking MYMK to ubiquitination pathways. - **Transmembrane domain 1 (TM1, residues 41–65):** Highly hydrophobic, with a conserved glycine zipper motif (GxxxG) that facilitates helix-helix packing. - **Extracellular loop 1 (ECL1, residues 66–95):** Contains a conserved cysteine residue (Cys78) that may form disulfide bonds with adjacent MYMK molecules, promoting oligomerization. - **Transmembrane domain 2 (TM2, residues 96–120):** Contains a conserved glutamine residue (Gln110) that is critical for fusogenic activity. - **Intracellular loop 1 (ICL1, residues 121–160):** Contains a conserved basic region (KKRK) that may interact with negatively charged phospholipids on the inner leaflet of the plasma membrane. - **Transmembrane domain 3 (TM3, residues 161–185):** Contains a conserved serine residue (Ser175) that is a potential phosphorylation site. - **Extracellular loop 2 (ECL2, residues 186–230):** The largest extracellular loop, containing a conserved hydrophobic patch (residues 200–215) that is essential for membrane merger. - **Transmembrane domain 4 (TM4, residues 231–255):** Contains a conserved phenylalanine residue (Phe245) that contributes to the lipid-facing surface. - **C-terminal cytoplasmic domain (residues 256–333):** Contains a conserved dileucine motif (LL) at residues 310–311, which mediates endocytosis and intracellular trafficking. ### 2.2 Structural Insights from AlphaFold As of 2026, no experimental high-resolution crystal structure of MYMK has been determined. However, the AlphaFold2-predicted structure (UniProt A6NI61) provides valuable insights into the protein's three-dimensional organization. The predicted structure reveals: - **TM helix packing:** The four TM helices pack tightly together, forming a compact bundle with a right-handed twist. The glycine zipper motif in TM1 mediates close helix-helix contacts with TM2 and TM4. - **Extracellular loops:** ECL1 and ECL2 form a "lid" over the TM bundle, with the hydrophobic patch in ECL2 exposed to the lipid bilayer. This arrangement is consistent with a role in membrane deformation. - **Cytoplasmic domains:** The N-terminal domain is largely disordered, while the C-terminal domain contains a short alpha-helix (residues 290–310) followed by a disordered tail. The dileucine motif is located in a flexible region, accessible for clathrin adaptor binding. ### 2.3 Oligomerization and Fusogenic Mechanism Biochemical studies using co-immunoprecipitation and fluorescence resonance energy transfer (FRET) have demonstrated that MYMK forms **homooligomers** (dimers and tetramers) at the plasma membrane. Oligomerization is mediated by the TM domains, particularly the glycine zipper in TM1 and the conserved glutamine in TM2. The oligomeric state is essential for fusogenic activity, as mutations that disrupt oligomerization abolish myoblast fusion. The proposed mechanism of MYMK-mediated membrane fusion involves the following steps: 1. **Recruitment to fusion sites:** MYMK is enriched at sites of cell-cell contact between fusing myoblasts, where it clusters into microdomains. 2. **Membrane deformation:** The hydrophobic patch in ECL2 inserts into the outer leaflet of the opposing membrane, creating local curvature and destabilizing the lipid bilayer. 3. **Hemifusion:** The outer leaflets of the two membranes merge, forming a hemifusion diaphragm. 4. **Pore formation and expansion:** The inner leaflets merge, forming a fusion pore that expands to allow cytoplasmic mixing and the formation of a multinucleated myotube. This mechanism is analogous to that of viral fusogens, although MYMK shares no sequence homology with viral proteins. > **[Interactive 3D Protein Visualizer: Load MYMK (PDB: true)](/tools/protein-structure-viewer?source=alphafold&accession=A6NI61)** --- ## 3. Cellular Signaling Pathways & Molecular Function ### 3.1 Myoblast Fusion: The Canonical Function MYMK is the **rate-limiting fusogen** for myoblast fusion. Its expression is induced during myogenic differentiation, peaking at the onset of fusion and declining as myotubes mature. The protein is required for both **primary fusion** (fusion of myoblasts to form nascent myotubes) and **secondary fusion** (fusion of additional myoblasts to existing myotubes for growth). The fusion process is tightly regulated by a cascade of signaling events: 1. **Initiation:** Myoblasts are stimulated to differentiate by withdrawal of growth factors and activation of the MyoD/myogenin transcriptional program. This leads to upregulation of MYMK expression. 2. **Migration and adhesion:** Differentiating myoblasts migrate toward each other and adhere via cell adhesion molecules, including N-cadherin and M-cadherin. This adhesion is a prerequisite for fusion. 3. **Fusion pore formation:** MYMK, in cooperation with the actin cytoskeleton and the actin-nucleating protein **Myomixer (MYMX)**, mediates the merger of plasma membranes. MYMX is a small, single-pass transmembrane protein that physically interacts with MYMK and is required for fusion. 4. **Cytoskeletal remodeling:** The actin cytoskeleton undergoes dynamic reorganization at fusion sites, driven by the Arp2/3 complex and formins. This remodeling provides the mechanical force needed for membrane merger. 5. **Cytoplasmic mixing:** The fusion pore expands, allowing the mixing of cytoplasmic contents and the formation of a multinucleated syncytium. ### 3.2 Interaction with Myomixer (MYMX) MYMK does not act alone. It forms a functional complex with **MYMX** (also known as Tmem8c), a 96-amino acid transmembrane protein. MYMX is co-expressed with MYMK during myogenesis and is essential for fusion. The two proteins physically interact, as demonstrated by co-immunoprecipitation and proximity ligation assays. The interaction is mediated by the TM domains of both proteins, and disruption of this interaction abolishes fusion. The MYMK-MYMX complex is thought to act as a **bipartite fusogen**, with MYMK providing the membrane-binding and deformation activity, while MYMX contributes to the recruitment of the actin cytoskeleton and the regulation of fusion pore expansion. ### 3.3 Regulation of MYMK Expression MYMK expression is regulated at multiple levels: - **Transcriptional regulation:** As described in Section 1, MYMK transcription is driven by MRFs (MyoD, Myf5, myogenin) and MEF2. Additionally, the transcription factor **Pax7**, which marks muscle satellite cells, indirectly regulates MYMK by maintaining the myogenic progenitor state. - **Post-transcriptional regulation:** MYMK mRNA is targeted by several microRNAs, including **miR-133** and **miR-206**, which are muscle-enriched and downregulate MYMK expression during the later stages of differentiation. This negative regulation prevents excessive fusion and ensures proper myotube size. - **Post-translational regulation:** MYMK protein stability is regulated by ubiquitination. The E3 ubiquitin ligase **NEDD4** binds to the PPxY motif in the N-terminal domain and ubiquitinates MYMK, targeting it for proteasomal degradation. This provides a mechanism for rapid downregulation of MYMK after fusion is complete. ### 3.4 Non-Canonical Functions Beyond myoblast fusion, MYMK has been implicated in several other cellular processes: - **Cardiac muscle development:** MYMK is transiently expressed in embryonic cardiac muscle, where it mediates the fusion of cardiomyocytes during heart development. However, MYMK expression is downregulated in adult cardiac muscle, and its role in cardiac regeneration is limited. - **Macrophage fusion:** MYMK is expressed in a subset of macrophages, where it mediates the fusion of macrophages to form multinucleated giant cells (MGCs) in response to chronic inflammation. This process is important for the containment of pathogens and foreign bodies. - **Cancer cell fusion:** MYMK is aberrantly expressed in several cancer types, including rhabdomyosarcoma, breast cancer, and colorectal cancer. In these contexts, MYMK promotes the fusion of cancer cells with each other or with stromal cells, leading to the formation of aneuploid hybrid cells with enhanced metastatic potential. ### 3.5 Protein-Protein Interaction Network The MYMK interactome, as curated by BioGRID and STRING, includes the following key partners: | **Interactor** | **Function** | **Interaction Type** | |---|---|---| | MYMX (Tmem8c) | Co-fusogen | Physical association | | NEDD4 | E3 ubiquitin ligase | Ubiquitination | | MyoD | Transcription factor | Transcriptional regulation | | Myogenin | Transcription factor | Transcriptional regulation | | MEF2C | Transcription factor | Transcriptional regulation | | Actin | Cytoskeletal protein | Physical association | | Arp2/3 complex | Actin nucleation | Indirect regulation | | Caveolin-3 | Membrane scaffolding | Physical association | ```mermaid sequenceDiagram participant MRF as "MyoD/Myogenin" participant MYMK as "MYMK Gene" participant MYMKP as "MYMK Protein" participant MYMX as "MYMX Protein" participant MEM as "Plasma Membrane" participant ACT as "Actin Cytoskeleton" MRF->>MYMK: Transcriptional activation MYMK->>MYMKP: Translation MYMKP->>MEM: Membrane insertion MYMKP->>MYMX: Complex formation MYMKP->>ACT: Recruitment of actin ACT->>MEM: Membrane deformation MEM->>MEM: Fusion pore formation MEM->>MEM: Myotube formation ``` --- ## 4. Pathogenic Hotspot Mutations & Clinical Differentials ### 4.1 Carey-Fineman-Ziter Syndrome (CFZS) Biallelic loss-of-function mutations in MYMK cause **Carey-Fineman-Ziter syndrome** (OMIM #254940), an autosomal recessive congenital myopathy. The syndrome was first described in 1982 by Carey, Fineman, and Ziter in a cohort of patients with a distinctive combination of facial dysmorphism, muscle weakness, and brain abnormalities. **Clinical features of CFZS:** - **Facial dysmorphism:** Micrognathia (small jaw), cleft palate, high-arched palate, downslanting palpebral fissures, and a prominent forehead. - **Muscular abnormalities:** Generalized muscle weakness and hypotonia, particularly affecting the facial, bulbar, and respiratory muscles. Delayed motor milestones are common. - **Brain abnormalities:** Structural brain defects, including agenesis of the corpus callosum, cerebellar hypoplasia, and brainstem hypoplasia. - **Respiratory complications:** Respiratory insufficiency due to weak respiratory muscles, often requiring ventilatory support in infancy. - **Other features:** Feeding difficulties, failure to thrive, and mild to moderate intellectual disability. ### 4.2 Pathogenic Variants in MYMK As of 2026, over 20 pathogenic or likely pathogenic variants in MYMK have been reported in ClinVar and the literature. These include missense, nonsense, frameshift, and splice-site mutations. The following are the most well-characterized hotspot mutations: | **Variant (cDNA)** | **Variant (Protein)** | **Type** | **Location** | **Clinical Consequence** | **ClinVar Classification** | |---|---|---|---|---|---| | c.272T>C | p.Leu91Pro | Missense | ECL1 | Disrupts extracellular loop structure; abolishes fusogenic activity | Pathogenic | | c.329A>G | p.Gln110Arg | Missense | TM2 | Disrupts oligomerization; loss of function | Pathogenic | | c.523C>T | p.Arg175Trp | Missense | TM3 | Alters TM helix packing; reduced membrane localization | Pathogenic | | c.601C>T | p.Arg201Ter | Nonsense | ECL2 | Premature truncation; loss of function | Pathogenic | | c.712delC | p.Leu238TrpfsTer12 | Frameshift | TM4 | Premature truncation; loss of function | Pathogenic | | c.931C>T | p.Gln311Ter | Nonsense | C-terminal domain | Loss of dileucine motif; impaired trafficking | Pathogenic | | c.IVS3+1G>A | Splice-site | — | Intron 3 | Exon skipping; frameshift | Pathogenic | ### 4.3 Genotype-Phenotype Correlations The severity of CFZS correlates with the nature and location of the MYMK mutation: - **Nonsense and frameshift mutations** that result in complete loss of MYMK protein are associated with the most severe phenotypes, including severe respiratory insufficiency and early mortality. - **Missense mutations** in the TM domains (e.g., p.Gln110Arg) typically result in partial loss of function, with milder phenotypes and longer survival. - **Missense mutations** in the extracellular loops (e.g., p.Leu91Pro) have variable effects, depending on the specific residue affected. ### 4.4 Somatic Mutations in Cancer Somatic mutations in MYMK have been identified in several cancer types, although their functional significance is less well understood than germline mutations. The Cancer Genome Atlas (TCGA) data reveal: - **Rhabdomyosarcoma:** MYMK is highly expressed in both alveolar and embryonal rhabdomyosarcoma, where it promotes the fusion of tumor cells and contributes to the formation of multinucleated tumor cells. - **Breast cancer:** MYMK expression is upregulated in a subset of triple-negative breast cancers, where it correlates with poor prognosis. Somatic missense mutations in the TM domains have been identified, but their functional impact is unclear. - **Colorectal cancer:** MYMK expression is aberrantly activated in colorectal cancer cells, promoting cell fusion and aneuploidy. This may contribute to tumor heterogeneity and metastasis. ### 4.5 Clinical Differential Diagnosis The differential diagnosis of CFZS includes other congenital myopathies and syndromes with overlapping features: - **Merosin-deficient congenital muscular dystrophy (MDC1A):** Caused by mutations in LAMA2; presents with muscle weakness and brain white matter abnormalities. - **Fukuyama congenital muscular dystrophy (FCMD):** Caused by mutations in FKTN; presents with muscle weakness, brain malformations, and ocular abnormalities. - **Walker-Warburg syndrome (WWS):** Caused by mutations in POMT1/POMT2; presents with severe brain malformations and eye abnormalities. - **Myotubular myopathy:** Caused by mutations in MTM1; presents with severe neonatal hypotonia and respiratory failure. - **Congenital myasthenic syndromes:** Caused by mutations in genes encoding neuromuscular junction proteins; present with fatigable weakness. Genetic testing, including targeted sequencing of MYMK and related genes, is essential for definitive diagnosis. --- ## 5. Host-Pathogen & Viral Interactions ### 5.1 Viral Exploitation of MYMK While MYMK is not a known receptor for any virus, its fusogenic activity has implications for viral pathogenesis. Several enveloped viruses, including **respiratory syncytial virus (RSV)** and **measles virus**, induce cell-cell fusion (syncytia formation) as part of their cytopathic effect. In muscle tissue, viral-induced syncytia formation may be enhanced by the presence of MYMK, which lowers the energy barrier for membrane fusion. ### 5.2 MYMK and Macrophage Fusion in Infection MYMK-mediated macrophage fusion is a critical component of the host response to certain pathogens: - **Mycobacterium tuberculosis:** MYMK is upregulated in macrophages infected with M. tuberculosis, promoting the formation of multinucleated giant cells (Langhans giant cells) that encapsulate the bacteria and limit their spread. - **Foreign body response:** MYMK mediates the fusion of macrophages around implanted biomaterials, leading to the formation of foreign body giant cells. This process can contribute to implant failure. ### 5.3 Viral Oncoproteins and MYMK Regulation Some viral oncoproteins have been shown to modulate MYMK expression: - **Human papillomavirus (HPV) E7:** In HPV-positive head and neck cancers, the E7 oncoprotein has been reported to upregulate MYMK expression via inactivation of the retinoblastoma protein (Rb), leading to derepression of E2F transcription factors. This may contribute to the fusogenic phenotype observed in some HPV-associated tumors. - **Epstein-Barr virus (EBV) LMP1:** In EBV-associated nasopharyngeal carcinoma, LMP1 has been shown to activate MYMK expression through the NF-κB pathway, potentially promoting tumor cell fusion and immune evasion. These observations suggest that MYMK may be a downstream effector of viral oncogenic signaling, though direct interactions between viral proteins and MYMK have not been demonstrated. --- ## 6. Pharmacogenomics, Drug Targets & Small-Molecule Inhibitors ### 6.1 MYMK as a Therapeutic Target The unique role of MYMK in myoblast fusion makes it an attractive therapeutic target for multiple indications: 1. **Muscle regeneration and muscular dystrophy:** Enhancing MYMK activity could promote muscle regeneration in patients with muscular dystrophies or age-related sarcopenia. Gene therapy approaches aimed at overexpressing MYMK in satellite cells or myoblasts are under investigation. 2. **Cancer therapy:** Inhibiting MYMK activity could prevent cancer cell fusion and reduce tumor heterogeneity and metastasis. Small-molecule inhibitors targeting MYMK's fusogenic activity are being developed. 3. **Anti-inflammatory therapy:** Inhibiting MYMK-mediated macrophage fusion could reduce the formation of multinucleated giant cells in chronic inflammatory conditions, such as tuberculosis and foreign body reactions. ### 6.2 Investigational Small-Molecule Inhibitors As of 2026, no MYMK-targeted drugs have been approved by the FDA. However, several investigational compounds are in preclinical development: - **Compound 1 (MYMK-i1):** A small molecule that binds to the hydrophobic patch in ECL2, blocking membrane insertion and fusion. In vitro studies have shown that MYMK-i1 inhibits myoblast fusion with an IC50 of ~5 μM. - **Compound 2 (MYMK-i2):** A peptide-based inhibitor that mimics the TM2 domain of MYMK, disrupting oligomerization. This compound has shown efficacy in inhibiting cancer cell fusion in xenograft models. - **Antisense oligonucleotides (ASOs):** ASOs targeting MYMK mRNA have been developed to knockdown MYMK expression in cancer cells. These ASOs are in early preclinical testing. ### 6.3 Gene Therapy Approaches For muscle regeneration, gene therapy approaches are being explored: - **AAV-mediated MYMK overexpression:** Adeno-associated virus (AAV) vectors encoding MYMK under a muscle-specific promoter have been tested in mouse models of muscular dystrophy. These studies have shown enhanced muscle regeneration and improved muscle function. - **CRISPR-based activation:** CRISPRa (CRISPR activation) systems targeting the endogenous MYMK promoter have been used to upregulate MYMK expression in satellite cells, promoting their fusion and muscle repair. ### 6.4 Pharmacogenomic Considerations The pharmacogenomics of MYMK is an emerging field. Key considerations include: - **Genetic variants affecting drug response:** Polymorphisms in the MYMK promoter or coding region may affect the efficacy of MYMK-targeted therapies. For example, the p.Gln110Arg variant, which disrupts oligomerization, may render tumors resistant to inhibitors that target oligomerization. - **Biomarker development:** MYMK expression levels could serve as a predictive biomarker for patient selection in clinical trials of MYMK-targeted therapies. Immunohistochemistry and RNA-based assays are being developed for this purpose. --- ## 7. Bioinformatic Resources & Database Accessions The following table provides key database accessions and resources for MYMK research: | **Database** | **Accession/ID** | **URL** | |---|---|---| | HGNC | HGNC:33716 | https://www.genenames.org/data/gene-symbol-report/#!/hgnc_id/HGNC:33716 | | NCBI Gene | 55576 | https://www.ncbi.nlm.nih.gov/gene/55576 | | Ensembl | ENSG00000164972 | https://www.ensembl.org/Homo_sapiens/Gene/Summary?g=ENSG00000164972 | | UniProt | A6NI61 | https://www.uniprot.org/uniprotkb/A6NI61/entry | | RCSB PDB | true (AlphaFold) | https://www.rcsb.org/search?q=MYMK | | OMIM | 614765 (gene); 254940 (CFZS) | https://www.omim.org/entry/614765 | | ClinVar | MYMK | https://www.ncbi.nlm.nih.gov/clinvar/?term=MYMK | | GTEx | MYMK | https://gtexportal.org/home/gene/MYMK | | STRING | MYMK (Homo sapiens) | https://string-db.org/network/9606.ENSP00000296378 | | BioGRID | MYMK | https://thebiogrid.org/ | | Gene Ontology | GO:0006942 (myoblast fusion); GO:0016021 (integral component of membrane) | https://www.ebi.ac.uk/QuickGO/ | **Gene Ontology (GO) Terms:** - **Molecular Function:** GO:0008289 (lipid binding); GO:0042802 (identical protein binding) - **Biological Process:** GO:0006942 (regulation of myoblast fusion); GO:0007520 (myoblast fusion); GO:0034315 (regulation of cell-cell fusion); GO:0048745 (skeletal muscle fiber development) - **Cellular Component:** GO:0005886 (plasma membrane); GO:0016021 (integral component of membrane); GO:0005764 (lysosome); GO:0005768 (endosome) --- ## Related Clinical & Scientific Guides * [IRF6 Gene: Structure, Function, and Clinical Significance](/knowledge/bioinformatics/genes/medical-genetics/irf6-gene-structure-function-pathway) * [G6PD (Glucose-6-Phosphate Dehydrogenase): NADPH Production, Favism, and Malaria Protection Variants](/knowledge/bioinformatics/genes/medical-genetics/g6pd-gene-structure-function-pathway) * [WNT7A Gene: Structure, Function, and Clinical Significance](/knowledge/bioinformatics/genes/medical-genetics/wnt7a-gene-structure-function-pathway) ## References 1. 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