Multi‐functional DNA proteins in yeast: The factors GFI and GFII are identical to the ARS‐binding factor ABFI and the centromere‐binding factor CPF1 respectively

GFI and GFII are abundant DNA‐binding proteins in the yeast Saccharomyces cerevisiae. Binding sites for GFI conform to the sequence 5′‐RTCRYNNNNNACG‐3′. This consensus can also accommodate the recognition sequence for the ARS1‐binding factor ABFI. Results of retardation‐competition assays, limited proteolysis experiments, molecular weight determinations based on denaturation–renaturation procedures and mobility shift assays of protein–DNA complexes formed in the presence of a monoclonal antibody raised against ABFI suggest strongly that GFI and ABFI are the same protein. Similarly, GFII appears to be identical to the centromere‐binding protein CPFI (alias CP1), since both proteins bind to the CDEI motif of yeast centromeres (5′‐RTCACRTG‐3′) and cannot be detected in a cpf1 disruption mutant yeast strain. In addition, based on denaturation–renaturation studies, both factors appear to have molecular weights in the same range of 53–62 kDa.