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TY - JOUR AU - Strohner, Ralf AU - Wachsmuth, Malte AU - Dachauer, Karoline AU - Mazurkiewicz, Jacek AU - Hochstatter, Julia AU - Rippe, Karsten AU - Längst, Gernot PY - 2005 DA - 2005/08/01 TI - A 'loop recapture' mechanism for ACF-dependent nucleosome remodeling JO - Nature Structural & Molecular Biology SP - 683 EP - 690 VL - 12 IS - 8 AB - The ATPase ISWI is the molecular motor of several nucleosome remodeling complexes including ACF. We analyzed the ACF-nucleosome interactions and determined the characteristics of ACF-dependent nucleosome remodeling. In contrast to ISWI, ACF interacts symmetrically with DNA entry sites of the nucleosome. Two-color fluorescence cross-correlation spectroscopy measurements show that ACF can bind four DNA duplexes simultaneously in a complex that contains two Acf1 and ISWI molecules. Using bead-bound nucleosomal substrates, nucleosome movement by mechanisms involving DNA twisting was excluded. Furthermore, an ACF-dependent local detachment of DNA from the nucleosome was demonstrated in a novel assay based on the preferred intercalation of ethidium bromide to free DNA. The findings suggest a loop recapture mechanism in which ACF introduces a DNA loop at the nucleosomal entry site that propagates over the histone octamer surface and leads to nucleosome repositioning. SN - 1545-9985 UR - https://doi.org/10.1038/nsmb966 DO - 10.1038/nsmb966 ID - Strohner2005 ER -