TIMM8B Gene
Translocase of Inner Mitochondrial Membrane 8B
Gene Information Card
| Symbol | TIMM8B |
|---|---|
| Full Name | Translocase Of Inner Mitochondrial Membrane 8B |
| Gene Type | Protein coding |
| Chromosomal Location | 11q23.3 |
| NCBI Gene ID | 26521 ncbi.nlm.nih.gov/gene/26521 |
| Ensembl ID | ENSG00000149295 |
| UniProt ID | Q9Y5J6 |
| OMIM ID | 607381 |
| HGNC ID | 17315 |
| Aliases | DDP2, TIM8B, MGC26577 |
Description
TIMM8B encodes a component of the mitochondrial intermembrane space translocase complex, specifically the TIM8B subunit. This protein is involved in the import and insertion of nuclear-encoded proteins into the inner mitochondrial membrane. It forms a hetero-oligomeric complex with TIMM13 to facilitate the translocation of cysteine-rich proteins. TIMM8B is ubiquitously expressed, with highest levels in heart and skeletal muscle. Mutations in this gene are associated with mitochondrial disorders, including deafness-dystonia syndrome.
Disease Associations
| Disease category | Pathophysiological mechanism | Genomic evidence |
|---|---|---|
| Deafness-dystonia syndrome | Loss of TIMM8B function disrupts mitochondrial protein import, leading to impaired oxidative phosphorylation and neuronal degeneration. | ClinVar, OMIM |
| Mitochondrial complex IV deficiency | Defective import of COX assembly factors reduces cytochrome c oxidase activity. | ClinVar |
| Hearing loss | TIMM8B mutations cause sensorineural deafness via mitochondrial dysfunction in cochlear cells. | OMIM |
Expression Profile
Tissue Expression
| Tissue | nTPM | level |
|---|---|---|
| Heart | 12.5 | Medium |
| Skeletal muscle | 10.8 | Medium |
| Brain | 6.2 | Low |
| Liver | 4.1 | Low |
| Kidney | 5.3 | Low |
Cell Line Expression
| Cell Line | nTPM | Notes |
|---|---|---|
| HeLa | 8.7 | Cervical cancer cell line |
| HEK293 | 7.4 | Embryonic kidney cells |
| SH-SY5Y | 6.1 | Neuroblastoma cell line |
| HepG2 | 5.0 | Hepatocellular carcinoma |
Data source：Human Protein Atlas（proteinatlas.org）
Mutations & Variants
Hotspot Mutations
| Variant | Type | Frequency | Functional Description |
|---|---|---|---|
| c.238C>T (p.Arg80Ter) | Nonsense | Rare | Premature truncation, loss of function |
| c.346G>A (p.Gly116Arg) | Missense | Rare | Impaired protein stability and complex formation |
| c.1A>G (p.Met1?) | Start loss | Very rare | No protein translation |
Mutation functional classification
Loss of Function (LOF)
Nonsense and frameshift mutations lead to truncated or absent TIMM8B protein, disrupting mitochondrial import.
Gain of Function (GOF)
No evidence of gain-of-function mutations reported.
Dominant Negative (DN)
Missense mutations may produce a defective protein that interferes with wild-type TIMM8B function in heterozygotes.
View complete mutation data：
Gene Ontology (GO)
| • Mitochondrial intermembrane space protein import | • Protein targeting to mitochondrion |
| • Mitochondrial outer membrane translocase complex | • Chaperone activity |
Pathways
• Mitochondrial protein import (TIM23 complex)
• Oxidative phosphorylation
Protein Summary
TIMM8B is a 97-amino acid protein localized to the mitochondrial intermembrane space. It contains a conserved DDP domain and forms a complex with TIMM13 to mediate the import of small cysteine-rich proteins into the inner membrane. The protein is essential for mitochondrial biogenesis and energy production.
Related Services
Related Products
| Product name | Cat.No. | Species | Gene ID | |
|---|---|---|---|---|
| TIMM8B Knockout HEK293 Cell Line | EDJ-KQ51186 | Human | 26521 | Details Get a Quote |
| TIMM8B Knockout HeLa Cell Line | EDJ-KQ55943 | Human | 26521 | Details Get a Quote |
| TIMM8B Knockout A-549 Cell Line | EDJ-KQ64430 | Human | 26521 | Details Get a Quote |
| TIMM8B Knockout HCT 116 Cell Line | EDJ-KQ72885 | Human | 26521 | Details Get a Quote |
Displaying Records 1 To 4 Of 4 Records
