Schnitzler G, Sif S, Kingston R E
Department of Molecular Biology, Massachusetts General Hospital, Boston 02114, USA.
Cell. 1998 Jul 10;94(1):17-27. doi: 10.1016/s0092-8674(00)81217-9.
The human SWI/SNF complex remodels nucleosome structure in an ATP-dependent manner, although the nature of this change has not been determined. Here we show that hSWI/SNF and ATP generate an altered nucleosomal structure that is stable in the absence of SWI/SNF. This product has an altered sensitivity to digestion by DNAse, restriction enzymes, and micrococcal nuclease, and an increased affinity for GAL4. It has the same protein composition but is approximately twice the size of a normal nucleosome. Incubation of the altered nucleosome with hSWI/SNF converts this structure back to a standard nucleosome in an ATP-dependent process. These results suggest that hSWI/ SNF acts by facilitating an exchange between normal and altered, more accessible, nucleosome conformations.
人类SWI/SNF复合物以ATP依赖的方式重塑核小体结构，尽管这种变化的本质尚未确定。在这里，我们表明hSWI/SNF和ATP会产生一种改变的核小体结构，该结构在没有SWI/SNF的情况下是稳定的。这种产物对DNA酶、限制性内切酶和微球菌核酸酶的消化敏感性发生了改变，并且对GAL4的亲和力增加。它具有相同的蛋白质组成，但大小约为正常核小体的两倍。将改变后的核小体与hSWI/SNF一起孵育，会在ATP依赖的过程中将这种结构恢复为标准核小体。这些结果表明，hSWI/SNF通过促进正常和改变后的、更易接近的核小体构象之间的交换来发挥作用。
