COOCCURRENCE OF CARG BOXES AND TCF SITES WITHIN VIRAL GENOMES

The transcription factor SRF is involved in the transduction of extrac ellular signals into nuclear responses, often in conjunction with tern ary complex factors (TCFs). Here we report the identification of CArG box SRF binding-sites, and neighboring TCF binding-sites, in viral gen omes. SRF binds and recruits TCFs to CMV, RSV and HTLV-1 viral genomes . At least one of two specific CArG boxes occurred in cytomegaloviruse s in the 5' proximal region of the major immediate early gene, one alw ays accompanied by a TCF site. This conservation was striking since ne ither the flanking sequences nor the spacing to the CAP site were cons erved. Thus the ubiquitous SRF and TCF molecules may control events in the life cycle of viruses. (C) 1994 Academic Press, Inc.