Schild D, Glassner B J, Mortimer R K, Carlson M, Laurent B C
Division of Cell and Molecular Biology, Lawrence Berkeley Laboratory, Berkeley, CA 94720.
Yeast. 1992 May;8(5):385-95. doi: 10.1002/yea.320080506.
The RAD54 gene of Saccharomyces cerevisiae is involved in the recombinational repair of DNA damage. The predicted amino acid sequence of the RAD54 protein shows significant homologies with the yeast SNF2 protein, which is required for the transcriptional activation of a number of diversely regulated genes. These proteins are 31% identical in a 492-amino acid region that includes presumed nucleotide and Mg2+ binding sites. We noted previously that the SNF2 protein also shares homology with a partial open reading frame (ORF) that was reported with the sequence of an adjacent gene. This ORF also shares homology with the RAD54 protein. To test whether this ORF is involved in transcriptional activation or DNA repair, yeast strains deleted for part of it have been isolated. These strains do not show a Snf-like phenotype, but they are UV sensitive. This gene has been identified as RAD16, a gene involved in the excision repair of DNA damage. Analysis of the rad16 deletion mutations indicates that RAD16 encodes a non-essential function and is not absolutely required for excision repair. Outside the region of homology to RAD54 and SNF2, the predicted RAD16 protein contains a novel cysteine-rich motif that may bind zinc and that has been found recently in eleven other proteins, including the yeast RAD18 protein. The homologies between RAD16, RAD54 and SNF2 are also shared by several additional, recently isolated yeast and Drosophila genes.
酿酒酵母的RAD54基因参与DNA损伤的重组修复。RAD54蛋白的预测氨基酸序列与酵母SNF2蛋白显示出显著的同源性，SNF2蛋白是许多受不同调控基因转录激活所必需的。在一个包含推测的核苷酸和Mg2+结合位点的492个氨基酸区域中，这些蛋白质有31%的同一性。我们之前注意到，SNF2蛋白还与一个部分开放阅读框（ORF）具有同源性，该开放阅读框是与相邻基因的序列一起报道的。这个ORF也与RAD54蛋白具有同源性。为了测试这个ORF是否参与转录激活或DNA修复，已经分离出了部分缺失该基因的酵母菌株。这些菌株没有显示出Snf样表型，但它们对紫外线敏感。这个基因已被鉴定为RAD16，一个参与DNA损伤切除修复的基因。对rad16缺失突变的分析表明，RAD16编码一种非必需功能，并且不是切除修复绝对必需的。在与RAD54和SNF2同源的区域之外，预测的RAD16蛋白包含一个新的富含半胱氨酸的基序，该基序可能结合锌，并且最近在包括酵母RAD18蛋白在内的其他十一种蛋白质中也发现了。RAD16、RAD54和SNF2之间的同源性也被最近分离出的其他几个酵母和果蝇基因所共享。
