...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Biochemistry >Deciphering the mechanism of thermodynamic accommodation of telomeric oligonucleotide sequences by the Schizosaccharomyces pombe protection of telomeres 1 (Pot1pN) protein
【24h】

Deciphering the mechanism of thermodynamic accommodation of telomeric oligonucleotide sequences by the Schizosaccharomyces pombe protection of telomeres 1 (Pot1pN) protein

机译：通过粒子1（POT1PN）蛋白的Schizosaccharomyces Pombe保护来解密端粒寡核苷酸序列的热力学容纳机理

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Linear chromosomes terminate in specialized nucleoprotein structures called telomeres, which are required for genomic stability and cellular proliferation. Telomeres end in an unusual 3' single-strand overhang that requires a special capping mechanism to prevent inappropriate recognition by the DNA damage machinery. In Schizosaccharomyces pombe, this protective function is mediated by the Pot1 protein, which binds specifically and with high affinity to telomeric ssDNA. We have characterized the thermodynamics and accommodation of both cognate and noncognate telomeric single-stranded DNA (ssDNA) sequences by Pot1pN, an autonomous ssDNA-binding domain (residues 1-187) found in full-length S. pombe Pot1. Direct calorimetric measurements of cognate telomeric ssDNA binding to Pot1pN show favorable enthalpy, unfavorable entropy, and a negative heat-capacity change. Thermodynamic analysis of the binding of noncognate telomeric ssDNA to Pot1pN resulted in unexpected changes in free energy, enthalpy, and entropy. Chemical-shift perturbation and structural analysis of these bound noncognate sequences show that these thermodynamic changes result from the structural rearrangement of both Pot1pN and the bound oligonucleotide. These data suggest that the ssDNA-binding interface is highly dynamic and, in addition to the conformation observed in the crystal structure of the Pot1pN/d(GGTTAC) complex, capable of adopting alternative thermodynamically equivalent conformations.
机译：线性染色体终止于称为端粒的专用核蛋白结构，这是基因组稳定性和细胞增殖所必需的。端粒在一个不寻常的3'单股突起中结束，需要一种特殊的封盖机制，以防止DNA损伤机械的不恰当识别。在Schizosaccharomyces Pombe中，该保护功能由Pot1蛋白介导，该蛋白质特别结合并具有高亲和力的端粒SsDNA。我们已经表征了通过pot1pn，在全长S.Pombe pot1中发现的自主SSDNA结合结构域（残基1-187）的热力学和非认知立体单链DNA（SSDNA）序列的热力学和容纳。对同源立体SSDNA结合到POT1PN的直接量热测量显示出有利的焓，不利的熵和负热容量变化。非认知端粒体SSDNA与POT1PN结合的热力学分析导致​​自由能，焓和熵的意外变化。这些结合的非认知序列的化学变换扰动和结构分析表明，这些热力学变化是由POT1PN和结合寡核苷酸的结构重排产生的。这些数据表明SSDNA结合界面是高动态的，并且除了在POT1PN / D（GGTTAC）复合物的晶体结构中观察到的构象之外，能够采用替代的热力学上等效的构象。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号