Molecular analysis of a new evolutionarily conserved transcription factor, e(y)2, was carried out. The protein was detected in a complex of approximately 700 kDa contained in a Drosophila melanogaster transcription nuclear extract. The e(y)2 protein was shown to interact with components of the preinitiation transcription complex TFIID. Addition of e(y)2 to a transcription extract of HeLa cells increased transcription 4-5 times when chromatin, but not free DNA, was used as a template. Genetic analysis showed that the C-terminal amino acid residues of transcription factor TAFII40 are important for its interaction with e(y)2.