A VARIETY OF DNA-BINDING AND MULTIMERIC PROTEINS CONTAIN THE HISTONE FOLD MOTIF

The histone fold motif has previously been identified as a structural feature common to all four core histones and is involved in both histo ne-histone and histone-DNA interactions. Through the use of a novel mo tif searching method, a group of proteins containing the histone fold motif has been established, The proteins in this group are involved in a wide variety of functions related mostly to DNA metabolism. Most of these proteins engage in protein-protein or protein-DNA interactions, as do their core histone counterparts. Among these, the CCAAT-specifi c transcription factor CBF and its yeast homologue HAP are two example s of multimeric complexes with different component subunits that conta in the histone fold motif. The histone fold proteins are distantly rel ated, with a relatively small degree of absolute sequence similarity. It is proposed that these proteins may share a similar three-dimension al conformation despite the lack of significant sequence similarity.