| Modification Notes |
TFIID is a general transcription factor that facilitates the preinitiation complex assembly through direct interactions with the TATA promoter element. TFIID is a multisubunit complex consisting of a small TATA-binding polypeptide and other TBP-associated factors (TAFs). TAF II p105, also called TAF4B, is a cell-type specific transcriptional coactivator that is a component of the TFIID complex. Expressed primarily in B cells and ovarian granulosa cells, TAF II p105 can interact with OCBA/POU2AF1 to activate B cell-specific octamer-dependent transcription. Additionally, TAF II p105 plays an important role in coactivating the transcription factor NF-kappaB and is essential for activation of anti-apoptotic genes such as TNFAIP3. Through its C-terminal histone-fold domain, TAF II p105 can form a heterodimer with TAF12/TAF II p20 that can then form a transcriptional activating octamer with several other TAFs. This protein is localized to the nucleus with cytoplasmic export mediated by a CRM1-independent export pathway. There are two isoforms expressed by alternative splicing. |
