Figure 7.

Schematic representation of the TFIID composition within WT, Taf8 KO and patient cells. In WT cells holo-TFIID, containing TBP and 13 TAFs, including WT TAF8, is abundant in cells and drives faithful transcription. In Taf8 knockout cells, such as the mESCs described in Figure 4 of this study, loss of TAF8 results in impaired TFIID and no transcription. In contrast, in the patient fibroblasts either only partial TAF assemblies form, or the tiny (undetectable) amount of mutant TAF8 protein integrates into a TFIID-like complex. Either, or both of these complexes could mediate Pol II transcription initiation in patinet fibroblasts.