The Requirement for TFIID In Vivo

Genetic analysis in yeast confirms the importance of TAFs, as all (with the exception of yeast TAF14, a protein found in several transcription-related complexes) are essential for viability. However, the requirement for individual TAFs in general Pol II transcription is still unclear. Various 

In summary, the in vivo data indicate that there may be a differential requirement for individual TAFs, but in general, TBIID complex is probably required at most promoters for transcription initiation. Furthermore, experiments in metazoans indicate an important role for TAFs during developmental processes that require strictly regulated transcription patterns. 

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