Snf2 proteins are a family of helicase-like proteins that direct energy derived from ATP hydrolysis into the mechanical remodelling of chromatin structure . Chromatin remodelers constitute one specialized family within helicase Superfamily 2 (SF2), and were originally named for their ability to alter the position and structure of nucleosomes. The ATPase motor, called SWI2/SNF2 after the first chromatin remodeler studied, has been found in a wide range of proteins, not all of which target the nucleosome but are aimed at disrupting distinct protein-nucleic acid complexes. Members of the Snf2 family have been demonstrated to remodel and/or disrupt a variety of DNA:protein. Biochemical observations showed that Swi2/Snf2 enzymes have the ability to specifically translocate dsDNA and introduce superhelical torsion in topologically constrained systems. The crystal structure of the archaeal Swi2/Snf2 homolog SSO1653 in complex with dsDNA showed that motifs Ia and IIa each bind one of the two strands of the duplex, mainly via interactions with the sugar?Cphosphate backbone.
1. G. Hauk, G. D. Bowman, Structural insights into regulation and action of SWI2/SNF2 ATPases. Curr Opin Struct Biol 21, 719 (2011).
2. M. R. Singleton, M. S. Dillingham, D. B. Wigley, Structure and mechanism of helicases and nucleic acid translocases. Annu Rev Biochem 76, 23 (2007)
3. H. Shaked, N. Avivi-Ragolsky, A. A. Levy, Involvement of the Arabidopsis SWI2/SNF2 chromatin remodeling gene family in DNA damage response and recombination. Genetics 173, 985 (2006)