【作者】 洪亮；

【导师】 项光亚； 吴学记；

【作者基本信息】 华中科技大学 ， 药物化学， 2009， 硕士

【摘要】 在细胞内ATP依赖型的蛋白质选择性降解途径——泛素-蛋白酶体途径中,热休克蛋白70的C末端相互作用蛋白(CHIP)可以与热休克蛋白相互协同来降解细胞内错误折叠的蛋白质,CHIP被认为是一种E3泛素连接酶,负责细胞的质量控制。在癌细胞中,由于癌基因与抑癌基因的表达产物异常,必然导致细胞内ATP依赖型的蛋白质选择性降解途径——泛素-蛋白酶体途径的异常,CHIP的表达量也可能随之异常。对正常组织和癌组织中CHIP蛋白表达量的比较研究,有助于阐明泛素-蛋白酶体途径异常与肿瘤发生之间的关系,并且有助于肿瘤的早期诊断。我们从转录水平和翻译水平两个层次来研究CHIP在食管的正常组织及癌组织的表达量。在转录水平研究上,利用琼脂糖凝胶电泳及实时荧光定量PCR技术,对不同组织中的CHIP的mRNA转录量进行定性及定量比较研究;在翻译水平研究上,利用免疫组化技术,对不同组织中的CHIP蛋白量进行比较研究,从而对其在正常组织与癌组织的表达差异进行研究。通过以上三种技术的检测、比较,结果显示,CHIP蛋白在正常组织与癌组织中的表达,不管是在转录水平上,还是在翻译水平上均存在着巨大的差异性,这将有助于阐明细胞癌变过程中,泛素-蛋白酶体所起的作用,为药物化学中抗癌药物的合成寻找新的靶点提供理论和实验依据,也为将来药物合成新的小分子抗癌活性物质或开发新型癌症诊断、分型、治疗试剂提供新思路和指导。更多还原

【Abstract】 The C-terminus of Hsp70 interacting protein (CHIP) is being considered to be a cellular protein quality control E3 ubiquitin ligase because of its ability to degrade misfolded proteins in association with heat shock chaperones, serve as the ATP-dependent selective protein degradation pathway-ubiquitin proteasome pathway. In malignant cells, the oncogenes and anti-oncogenes are expressed abnormally, which induce the abnormality of the ubiquitin proteasome pathway necessarily, then the CHIP is expressed abnormally. Screening the expression profile of CHIP gene in normal tissues and cancer tissues will elucidate the relationship between the abnormality of ubiquitin proteasome pathway and the development of cancer; also it will be helpful for cancer diagnosis.We detected the expression profile of CHIP in normal tissues and cancer tissues from esophagus and stomach at two levels, one is the level of transcription, and another is the level of translation. At the level of transcription, we use the agarose gel electrophoresis and Real-time Qualititative RCR to analysis the amount of the mRNA of CHIP in different tissues; at the tanslation level, we use the technology of immunohistochemistry to detect the amount of CHIP in different tissues.We found that CHIP protein is overexpressed in transcription level and translation level in esophagus cancer. It demonstrated that CHIP expression in esophagus cancer might be regulated by transcriptional and translational mechanism. Our data implicate that CHIP may serve as a valuable molecular marker for esophagus cancer.更多还原