MYO3A
Myosin IIIA: A key actin-based motor protein in sensory hair cells
Gene Information Card
| Symbol | MYO3A |
|---|---|
| Full Name | Myosin IIIA |
| Gene Type | protein-coding |
| Chromosomal Location | 10p12.1 |
| NCBI Gene ID | 53904 ncbi.nlm.nih.gov/gene/53904 |
| Ensembl ID | ENSG00000136531 |
| UniProt ID | Q8NEV4 |
| OMIM ID | 606808 |
| HGNC ID | 7601 |
| Aliases | DFNB30, MYO3A, myosin IIIA |
Description
MYO3A encodes myosin IIIA, an unconventional myosin motor protein that uses actin filaments as tracks. It is predominantly expressed in inner ear hair cells and retinal photoreceptors, where it plays a critical role in the development and maintenance of stereocilia and phototransduction. Mutations in MYO3A cause autosomal recessive non-syndromic hearing loss (DFNB30) and have been implicated in Usher syndrome-like phenotypes. The protein contains an N-terminal kinase domain and a C-terminal myosin motor domain, enabling both signaling and mechanical functions.
Disease Associations
| Disease category | Pathophysiological mechanism | Genomic evidence |
|---|---|---|
| Autosomal recessive non-syndromic hearing loss 30 (DFNB30) | Loss-of-function mutations disrupt stereocilia actin bundle organization in cochlear hair cells | ClinVar, OMIM |
| Usher syndrome type 3 (USH3) – atypical | Possible digenic or modifier effects with other Usher genes | ClinVar, OMIM |
Expression Profile
Tissue Expression
| Tissue | nTPM | level |
|---|---|---|
| Cochlea | High | High |
| Retina | Moderate | Medium |
| Testis | Low | Low |
| Brain | Low | Low |
Cell Line Expression
| Cell Line | nTPM | Notes |
|---|---|---|
| HEK293 | Low | Transient expression studies |
| HeLa | Low | Minimal endogenous expression |
| Cochlear hair cell lines | High | Endogenous expression in sensory cells |
Data source：Human Protein Atlas（proteinatlas.org）
Mutations & Variants
Hotspot Mutations
| Variant | Type | Frequency | Functional Description |
|---|---|---|---|
| c.1045C>T (p.Arg349*) | Nonsense | Rare | Loss of function; truncation of motor domain |
| c.1616G>A (p.Arg539His) | Missense | Rare | Impaired ATPase activity |
| c.2413G>A (p.Gly805Arg) | Missense | Rare | Reduced actin binding |
Mutation functional classification
Loss of Function (LOF)
Nonsense and frameshift mutations leading to truncated protein or nonsense-mediated decay; cause DFNB30
Gain of Function (GOF)
Not reported
Dominant Negative (DN)
Not reported; all known pathogenic variants are recessive
View complete mutation data：
Gene Ontology (GO)
| • actin binding | • ATP binding |
| • calmodulin binding | • microtubule motor activity |
| • protein kinase activity | • actin filament-based movement |
| • sensory perception of sound | • photoreceptor cell maintenance |
Pathways
• Unconventional myosin pathway
• Stereocilia development
• Phototransduction
Protein Summary
Myosin IIIA is a 1615-amino acid protein with an N-terminal serine/threonine kinase domain, a central neck region with IQ motifs that bind calmodulin, and a C-terminal myosin motor domain. It localizes to the tips of stereocilia in inner ear hair cells and to the connecting cilium of photoreceptors. The kinase domain autophosphorylates and regulates motor activity, while the motor domain transports cargo along actin filaments. Defects in MYO3A lead to progressive hearing loss due to stereocilia degeneration.
Related Services
Related Products
| Product name | Cat.No. | Species | Gene ID | |
|---|---|---|---|---|
| MYO3A Knockout HEK293 Cell Line | EDJ-KQ11362 | Human | 53904 | Details Get a Quote |
| MYO3A Knockout HeLa Cell Line | EDJ-KQ56388 | Human | 53904 | Details Get a Quote |
| MYO3A Knockout A-549 Cell Line | EDJ-KQ64879 | Human | 53904 | Details Get a Quote |
| MYO3A Knockout HCT 116 Cell Line | EDJ-KQ73323 | Human | 53904 | Details Get a Quote |
