TFIIH - A KEY COMPONENT IN MULTIPLE DNA TRANSACTIONS

The transcription factor TFIIH is a versatile, multi-functional protei n complex with multiple engagements. Apart from its role in basal tran scription, TFIIH is intimately implicated in DNA repair and (probably) in cell cycle control (both of which are required to prevent carcinog enesis) as well as having possible roles in other processes. Thus, it is a striking example of the efficient use of one component for many p urposes. Ingeniously, the incorporation of this essential factor into important, but non-essential, mechanisms, such as DNA repair, protects against cancer. The critical role of TFIIH in transcription function renders inactivating TFIIH mutations lethal to cells. Without this tra nscription connection, such mutations would lead to genetic instabilit y and oncogenesis.