In vivo binding of Sp1/Sp3, USF-1, and NF-YA to the CBS −1b promoter.

Chromatin extracts of the CMK, CMS, and HepG2 (control) cell lines bound to transcription factor complexes were immunoprecipitated with Sp1, Sp3, USF-1, and NF-YA antisera. PCR amplifications were performed with seminested primers for the CBS −1b promoter region (positions −3921 to −3625), as described in “Materials and methods,” and the amplicons visualized on 2% agarose gels.