Two overlapping cDNAs that encode a 197-kDa sequence-selective DNA-binding 
protein were isolated from libraries derived from mouse lymphoid cell mRNA. In 
addition to a DNA-binding domain, the protein contains both a chromodomain, 
which occurs in proteins that are implicated in chromatin compaction, and an 
SNF2/SWI2-like helicase domain, which occurs in proteins that are believed to 
activate transcription by counteracting the repressive effects of chromatin 
structure. A Southern blot analysis indicated that this protein, which we have 
named CHD-1, for chromodomain-helicase-DNA-binding protein, is present in most, 
if not all, mammalian species. A Northern blot analysis revealed multiple CHD 
mRNA components that differed both qualitatively and quantitatively among 
various cell types. The various mRNAs, which are probably produced by 
alternative RNA processing, could conceivably encode tissue-specific and 
developmental stage-specific isoforms of the protein. Based on its interesting 
combination of features, we suspect that CHD-1 plays an important role in gene 
regulation.