Transcription initiation factor TFIID subunit 4B (TAF4B)
The protein contains 862 amino acids for an estimated molecular weight of 91091 Da.
Cell type-specific subunit of the general transcription factor TFIID that may function as a gene-selective coactivator in certain cells. TFIID is a multimeric protein complex that plays a central role in mediating promoter responses to various activators and repressors. TAF4B is a transcriptional coactivator of the p65/RELA NF-kappa-B subunit. Involved in the activation of a subset of antiapoptotic genes including TNFAIP3. May be involved in regulating folliculogenesis. Through interaction with OCBA/POU2AF1, acts as a coactivator of B-cell-specific transcription. Plays a role in spermiogenesis and oogenesis. (updated: Sept. 12, 2018)
Protein identification was indicated in the following studies:
Methods
The following articles were analysed to gather the proteome content of erythrocytes.
The gene or protein list provided in the studies were processed using the ID mapping API of Uniprot in September 2018. The number of proteins identified and mapped without ambiguity in these studies is indicated below.
Only Swiss-Prot entries (reviewed) were considered for protein evidence assignation.
| Publication | Identification 1 | Uniprot mapping 2 | Not mapped / Obsolete | TrEMBL | Swiss-Prot |
|---|---|---|---|---|---|
| Goodman (2013) | 2289 (gene list) | 2278 | 53 | 20599 | 2269 |
| Lange (2014) | 1234 | 1234 | 7 | 28 | 1224 |
| Hegedus (2015) | 2638 | 2622 | 0 | 235 | 2387 |
| Wilson (2016) | 1658 | 1528 | 170 | 291 | 1068 |
| d'Alessandro (2017) | 1826 | 1817 | 2 | 0 | 1815 |
| Bryk (2017) | 2090 | 2060 | 10 | 108 | 1942 |
| Chu (2018) | 1853 | 1804 | 55 | 362 | 1387 |
1 as available in the article and/or in supplementary material
2 uniprot mapping returns all protein isoforms as one entry
The compilation of older studies can be retrieved from the Red Blood Cell Collection database.
The data and differentiation stages presented below come from the proteomic study and analysis performed by our partners of the GReX consortium, more details are available in their published work.
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| Variant | Description |
|---|---|
| dbSNP:rs16942219 | |
| dbSNP:rs12963653 |
No binding partner found
The reference OMIM entry for this protein is 601689
Taf4b rna polymerase ii, tata box-binding protein-associated factor, 105-kd; taf4b
Tata box-binding protein-associated factor c2; taf2c2
Tbp-associated factor, rna polymerase ii, 105-kd; tafii105
CLONING
TATA-binding protein-associated factors (TAFs) participate, with TATA-binding protein (TBP; 600075), in the formation of the TFIID protein complex (see 313650), which is involved in the initiation of gene transcription by RNA polymerase II (see 180660). Dikstein et al. (1996) reported that differentiated B cells contain a novel substoichiometric TAF of 105 kD not found associated with TFIID isolated from other cell types. They purified the protein (called TAFII105 by them) and cloned the human gene from a Daudi cell cDNA library using PCR primers designed from the protein sequence. The cDNA revealed a highly conserved C-terminal domain shared by TAFII130 (TAF2C) and TAFII110 as well as a divergent N-terminal coactivator domain. All cells tested expressed TAFII105 mRNA but only B cells contained significant levels of the protein in association with TFIID. These and other properties of the protein suggested to Dikstein et al. (1996) that TAFII105 is a cell type-specific subunit of TFIID that may be responsible for mediating transcription by a subset of activators in B cells. See also TAF2C1 (601796).MAPPING
The International Radiation Hybrid Mapping Consortium mapped the TAF4B (TAF2C2) gene to chromosome 18 (TMAP Y09321).MOLECULAR GENETICS
In a consanguineous Turkish family in which 4 of 8 brothers were infertile due to spermatogenic failure (SPGF13; 615841), Ayhan et al. (2014) identified homozygosity for a nonsense mutation in the TAF4B gene (R611X; 601689.0001) that segregated with disease in the family and that was not found in controls.ANIMAL MODEL
Freiman et al. (2001) generated mice deficient in TAFII105 by targeted disruption. Female mice lacking TAFII105 are viable but infertile because of a defect in folliculogenesis correlating with restricted expression of TAFII105 in the granulosa cells of the ovarian follicle. Freiman et al. (2001) used gene expression profiling to uncover a defective inhibin-activin signaling pathway in TAFII105-deficient ovaries. Together, these studies suggested that TAFII105 mediates the transcription of a subset of genes required for proper folliculogenesis in the ovary and established TAFII105 as a cell type-specific component of the mammalian transcriptional machinery. TAFII105-deficient ovaries showed decreased expression of the following genes: inhibin beta-B (147390), aromatase p450, inhibin beta-A (147290), cyclin D2 (123833), 17-beta hydroxysteroid dehydrogenase I (109684), follistatin (136470), and inhibin-alpha (147380). Falender et al. (2005) found that male Taf4b-null mice were initially fertile, but they became infertile by 3 months of age and eventually exhibited germ cell loss and testicular degeneration. At birth, testes of Taf4b-null males appeared histologically normal; however, at postnatal day 3, gonocyte proliferation was impaired and expression of the spermatogonial stem cell markers Ret (164761), Plzf (ZNF145; 176797), and Stra8 (609987) was reduced. Falender et al. (2005) concluded that TAF4B is required for the regulation of spermatogonial stem cell specification and proliferation in the adult. ... More on the omim web site
Oct. 20, 2018: Protein entry updated
Automatic update: OMIM entry 601689 was added.
Oct. 19, 2018: Additional information
Initial protein addition to the database. This entry was referenced in Bryk and co-workers. (2017).