SWI2/SNF2 CHROMATIN-REMODELING DOMAIN OF EUKARYOTIC RAD54

本子项目是利用由NIH/NCRR资助的中心赠款提供的资源的众多研究子项目之一。子项目和研究者（PI）可能已经从另一个NIH来源获得了主要资金，因此可以在其他CRISP条目中表示。列出的机构是中心的，不一定是研究者的机构。SWI2/SNF2染色质重塑蛋白介导核小体和其他dna相关蛋白的动员。SWI2/SNF2蛋白含有SF2解旋酶特征的序列基序，但不具有解旋酶活性。相反，它们将ATP水解与DNA超螺旋扭转的产生结合在一起。斑马鱼Rad54核小体重塑结构域（参与rad51介导的同源重组的蛋白）的结构表明，SWI2/SNF2酶的核心由两个类似于SF2解旋酶的α / β -裂片组成。Rad54解旋酶裂片含有形成两个螺旋结构域的插入，每个裂片内各有一个螺旋结构域。这些插入包含SWI2/SNF2特异性序列基序，可能是SWI2/SNF2功能的核心。由两个裂片形成的宽间隙，两侧是螺旋插入，包含SWI2/SNF2蛋白中保守的残基和与SF2解旋酶结合dna有关的基序。Rad54结构表明SWI2/SNF2蛋白使用类似解旋酶的机制在dsDNA上转位。该研究结果发表在《自然-结构分子生物学》杂志上

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. SWI2/SNF2 chromatin-remodeling proteins mediate the mobilization of nucleosomes and other DNA-associated proteins. SWI2/SNF2 proteins contain sequence motifs characteristic of SF2 helicases but do not have helicase activity. Instead, they couple ATP hydrolysis with the generation of superhelical torsion in DNA. The structure of the nucleosome-remodeling domain of zebrafish Rad54, a protein involved in Rad51-mediated homologous recombination, reveals that the core of the SWI2/SNF2 enzymes consist of two alpha/beta-lobes similar to SF2 helicases. The Rad54 helicase lobes contain insertions that form two helical domains, one within each lobe. These insertions contain SWI2/SNF2-specific sequence motifs likely to be central to SWI2/SNF2 function. A broad cleft formed by the two lobes and flanked by the helical insertions contains residues conserved in SWI2/SNF2 proteins and motifs implicated in DNA-binding by SF2 helicases. The Rad54 structure suggests that SWI2/SNF2 proteins use a mechanism analogous to helicases to translocate on dsDNA. This work was published in Nature Structural Molecular Biology and the structure deposited in the PDB (1Z