Noselli S, Payre F, Vincent A
Centre de Recherche de Biochimie et de Génétique Cellulaires, Centre National de la Recherche Scientifique, Toulouse, France.
Mol Cell Biol. 1992 Feb;12(2):724-33. doi: 10.1128/mcb.12.2.724-733.1992.
The closely related Drosophila serendipity (sry) beta and delta zinc finger proteins display consensus in vitro DNA recognition sequences differing by 4 of 13 nucleotide positions and bind in vivo to distinct sets of sites on polytene chromosomes. We compared the pattern of in vivo chromosomal binding of deleted forms of the sry delta protein fused to beta-galactosidase and expressed in Drosophila transgenic lines. Results show that the carboxy-terminal DNA-binding finger domain is required and sufficient for binding at specific chromosomal sites but that this binding does not nearly reproduce the wild-type pattern. An NH2-terminal domain of the sry delta protein is essential to its specificity of in vivo interaction with chromatin. In vitro and in vivo experiments using reciprocal finger swap between the sry beta and delta proteins suggest that the in vivo specificity is dependent on selective protein-protein contacts at defined chromosomal sites, in addition to DNA specific recognition.
密切相关的果蝇意外（sry）β和δ锌指蛋白在体外DNA识别序列上具有一致性，13个核苷酸位置中有4个不同，并且在体内与多线染色体上不同的位点集合结合。我们比较了与β-半乳糖苷酶融合并在果蝇转基因系中表达的sryδ蛋白缺失形式的体内染色体结合模式。结果表明，羧基末端DNA结合指结构域对于在特定染色体位点结合是必需的且足够的，但这种结合几乎不能重现野生型模式。sryδ蛋白的NH2末端结构域对其与染色质体内相互作用的特异性至关重要。使用sryβ和δ蛋白之间的相互指交换进行的体外和体内实验表明，除了DNA特异性识别外，体内特异性还取决于在特定染色体位点的选择性蛋白质-蛋白质接触。
