TAF8: TATA-Box Binding Protein Associated Factor 8
A core component of the TFIID complex involved in RNA polymerase II transcription initiation and neurodevelopmental disorders.
Gene Information Card
| Symbol | TAF8 |
|---|---|
| Full Name | TATA-box binding protein associated factor 8 |
| Gene Type | Protein coding |
| Chromosomal Location | 6p21.1 |
| NCBI Gene ID | 129685 ncbi.nlm.nih.gov/gene/129685 |
| Ensembl ID | ENSG00000137413 |
| UniProt ID | Q7Z7C8 |
| OMIM ID | 609532 |
| HGNC ID | 17300 |
| Aliases | TAFII43, TAF(II)43, MRT26 |
Description
TAF8 encodes a subunit of the transcription factor IID (TFIID) complex, which is essential for RNA polymerase II-mediated transcription initiation. The protein contains a histone-fold domain that mediates interactions with other TFIID subunits and contributes to promoter recognition and transcription start site selection. TAF8 is ubiquitously expressed and plays a critical role in embryonic development, particularly in the central nervous system. Mutations in TAF8 cause autosomal recessive intellectual disability and neurodevelopmental abnormalities.
Disease Associations
| Disease category | Pathophysiological mechanism | Genomic evidence |
|---|---|---|
| Intellectual disability, autosomal recessive 26 (MRT26) | Loss-of-function mutations in TAF8 impair TFIID complex assembly and transcription of genes required for neuronal development. | ClinVar, OMIM |
| Neurodevelopmental disorder with hypotonia and brain abnormalities | Homozygous missense and frameshift variants disrupt TAF8 protein stability and TFIID function. | ClinVar, OMIM |
Expression Profile
Tissue Expression
| Tissue | nTPM | level |
|---|---|---|
| Brain (cerebral cortex) | 12.5 | Medium |
| Testis | 10.2 | Medium |
| Heart | 8.9 | Medium |
| Liver | 6.3 | Low |
| Kidney | 7.1 | Low |
Cell Line Expression
| Cell Line | nTPM | Notes |
|---|---|---|
| HEK293 | 14.3 | Embryonic kidney cells; high expression |
| SH-SY5Y | 11.8 | Neuroblastoma cell line; relevant for neuronal studies |
| HeLa | 9.5 | Cervical carcinoma cells; moderate expression |
Data source：Human Protein Atlas（proteinatlas.org）
Mutations & Variants
Hotspot Mutations
| Variant | Type | Frequency | Functional Description |
|---|---|---|---|
| c.1A>G (p.Met1?) | Start loss | Rare | Loss of translation initiation; likely null allele |
| c.304C>T (p.Arg102Trp) | Missense | Rare | Disrupts histone-fold domain; reduced protein stability |
| c.626_627del (p.Glu209Glyfs*12) | Frameshift | Rare | Premature truncation; loss of function |
Mutation functional classification
Loss of Function (LOF)
Homozygous or compound heterozygous loss-of-function mutations (e.g., start loss, frameshift) cause TAF8 deficiency, leading to impaired TFIID assembly and transcription defects.
Gain of Function (GOF)
No gain-of-function mutations reported for TAF8.
Dominant Negative (DN)
No dominant-negative mutations reported; disease inheritance is autosomal recessive.
View complete mutation data：
Gene Ontology (GO)
| • transcription factor TFIID complex (GO:0005669) | • DNA-templated transcription initiation (GO:0006352) |
| • DNA binding (GO:0003677) | • protein binding (GO:0005515) |
| • nucleus (GO:0005634) |
Pathways
• RNA polymerase II transcription initiation (Reactome: R-HSA-75953)
• TFIID assembly (Reactome: R-HSA-109581)
Protein Summary
TAF8 is a 43 kDa protein that contains a conserved histone-fold domain (HFD) at its N-terminus, which mediates heterodimerization with TAF10. This interaction is crucial for the structural integrity of the TFIID complex. TAF8 also interacts with TAF6 and TAF9. The protein is localized to the nucleus and is required for transcription of a subset of genes, including those involved in cell cycle regulation and neurodevelopment. Alternative splicing generates multiple transcript variants, but the functional significance of isoforms is not fully characterized.
Related Services
Related Products
| Product name | Cat.No. | Species | Gene ID | |
|---|---|---|---|---|
| TAF8 Knockout HEK293 Cell Line | EDJ-KQ51971 | Human | 129685 | Details Get a Quote |
| TAF8 Knockout HeLa Cell Line | EDJ-KQ58266 | Human | 129685 | Details Get a Quote |
| TAF8 Knockout A-549 Cell Line | EDJ-KQ66753 | Human | 129685 | Details Get a Quote |
| TAF8 Knockout HCT 116 Cell Line | EDJ-KQ75160 | Human | 129685 | Details Get a Quote |
