Recruits TFIIH to the initiation complex and stimulates the RNA polymerase II C-terminal domain kinase and DNA-dependent ATPase activities of TFIIH. Both TFIIH and TFIIE are required for promoter clearance by RNA polymerase (By similarity). TFIIE is a tetramer of two alpha (TFA1) and two beta (TFA2) subunits. Present with 35900 molecules/cell in log phase SD medium. Belongs to the TFIIE alpha subunit family.