SNF2 is a yeast transcriptional activator protein, the first described of the SNF2 family, consisting of SNF2 and its homologs. All proteins in the family contain sequence motifs of significant similarity to the DNA and RNA helicase protein families (PMID:17526749). SNF2 is the ATPase component of the SWI/SNF2 chromatin remodelling complex, which utilises energy derived from ATP hydrolysis to disrupt histone-DNA interactions to allow transcriptional machinery access to DNA.