MYO1B
Myosin IB: An actin-based motor protein involved in membrane trafficking and cell motility
Gene Information Card
| Symbol | MYO1B |
|---|---|
| Full Name | myosin IB |
| Gene Type | protein coding |
| Chromosomal Location | 2q32.3 |
| NCBI Gene ID | 4430 ncbi.nlm.nih.gov/gene/4430 |
| Ensembl ID | ENSG00000115947 |
| UniProt ID | O43795 |
| OMIM ID | 606537 |
| HGNC ID | 7596 |
| Aliases | myosin-1B, MYH-1b, MMIa, MMIb |
Description
MYO1B encodes myosin IB, a member of the class I myosin family of actin-based motor proteins. It is involved in membrane trafficking, endocytosis, and cell migration by linking actin filaments to cellular membranes. The protein contains a motor domain, a neck region with IQ motifs for calmodulin binding, and a tail domain that interacts with phospholipids and other proteins. MYO1B is widely expressed and plays roles in cytoskeletal dynamics and signal transduction.
Disease Associations
| Disease category | Pathophysiological mechanism | Genomic evidence |
|---|---|---|
| Hearing loss, autosomal dominant 67 | Missense mutations in MYO1B disrupt actin-based stereocilia function in inner ear hair cells | ClinVar, OMIM |
| Colorectal cancer | Overexpression and copy number gains of MYO1B associated with tumor progression and metastasis | COSMIC, NCBI |
| Breast cancer | Altered MYO1B expression linked to invasive phenotype and poor prognosis | COSMIC, NCBI |
Expression Profile
Tissue Expression
| Tissue | nTPM | level |
|---|---|---|
| Brain | 12.5 | Medium |
| Lung | 8.3 | Low |
| Liver | 6.1 | Low |
| Kidney | 15.2 | Medium |
| Testis | 20.4 | High |
| Spleen | 9.7 | Low |
Cell Line Expression
| Cell Line | nTPM | Notes |
|---|---|---|
| HeLa | 18.5 | Cervical cancer cell line |
| A549 | 14.2 | Lung carcinoma cell line |
| HEK293 | 22.1 | Embryonic kidney cell line |
| MCF7 | 11.3 | Breast cancer cell line |
Data source：Human Protein Atlas（proteinatlas.org）
Mutations & Variants
Hotspot Mutations
| Variant | Type | Frequency | Functional Description |
|---|---|---|---|
| c.2215C>T (p.Arg739Cys) | Missense | 0.01% (gnomAD) | Associated with autosomal dominant hearing loss; alters motor domain function |
| c.2872G>A (p.Gly958Arg) | Missense | 0.005% (gnomAD) | Reported in ClinVar as likely pathogenic for hearing loss |
| c.1234_1236del (p.Lys412del) | In-frame deletion | 0.002% (COSMIC) | Found in colorectal cancer; may affect actin binding |
Mutation functional classification
Loss of Function (LOF)
Loss-of-function mutations in MYO1B, such as nonsense or frameshift variants, are rare and may impair actin-based motility and membrane trafficking, potentially contributing to hearing loss or cancer progression.
Gain of Function (GOF)
Gain-of-function mutations in MYO1B are not well characterized; however, overexpression in cancers suggests possible oncogenic gain-of-function effects.
Dominant Negative (DN)
Dominant-negative mutations, particularly missense changes in the motor domain, can disrupt myosin IB function and are implicated in autosomal dominant hearing loss.
View complete mutation data：
Gene Ontology (GO)
| • actin binding | • ATP binding |
| • calmodulin binding | • microtubule motor activity |
| • actin filament binding | • phosphatidylinositol binding |
| • cytoskeleton | • membrane |
Pathways
• Actin cytoskeleton regulation
• Endocytosis
• Fc gamma R-mediated phagocytosis
• Cell migration
Protein Summary
Myosin IB is a single-headed, non-filamentous myosin that functions as an actin-based motor. It transports vesicles and organelles along actin filaments, anchors actin to membranes, and is critical for processes such as endocytosis, exocytosis, and cell motility. The protein is composed of an N-terminal motor domain that hydrolyzes ATP to generate force, a neck region that binds calmodulin, and a C-terminal tail that targets membranes via lipid interactions. MYO1B is ubiquitously expressed with highest levels in testis, brain, and kidney. Mutations in MYO1B cause autosomal dominant hearing loss (DFNA67) and are implicated in cancer progression.
Related Services
Related Products
| Product name | Cat.No. | Species | Gene ID | |
|---|---|---|---|---|
| MYO1B Knockout HEK293 Cell Line | EDJ-KQ5240 | Human | 4430 | Details Get a Quote |
| MYO1B Knockout A-549 Cell Line | EDJ-KQ27033 | Human | 4430 | Details Get a Quote |
| MYO1B Knockout HCT 116 Cell Line | EDJ-KQ28272 | Human | 4430 | Details Get a Quote |
| MYO1B Knockout HeLa Cell Line | EDJ-KQ28273 | Human | 4430 | Details Get a Quote |
