论文部分内容阅读
角膜环状皮样瘤(RDC)是一种呈常染色体显性遗传的角膜良性肿瘤,前期研究证明,PITX2基因的G185A突变(R62H)是导致RDC发生的原因.为了进一步探讨R62H导致RDC的分子基础,将PITX2构建至原核表达载体,诱导表达后纯化融合蛋白进行EMSA实验,显示R62H与DNA的结合能力并未明显下降.筛选稳定表达PITX2WT和R62H的HeLa细胞克隆,用流式细胞仪分析细胞周期,并用Quantitative Real-time PCR来检测细胞克隆的β-catenin和Cyclin D1的表达水平,结果发现稳定表达PITX2R62H的HeLa细胞的增殖活性低于PITX2WT,且β-catenin和CyclinD1的mRNA水平均比PITX2WT明显下降.由此推测,R62H突变使Wnt/β-catenin→PITX2信号途径发生改变,促使基因表达异常,导致细胞异常增生和角膜环状皮样瘤的形成.
Corneal ring-like dermoid tumor (RDC) is an autosomal dominant corneal benign tumor, previous studies have shown that, PITX2 gene G185A mutation (R62H) is the cause of RDC occurred in order to further explore the R62H cause RDC molecules PITX2 was constructed into prokaryotic expression vector, and the fusion protein was purified and induced by EMSA.It showed that the binding ability of R62H and DNA did not decrease obviously.The HeLa cells stably expressing PITX2WT and R62H were screened and analyzed by flow cytometry The results showed that the proliferation activity of HeLa cells stably expressing PITX2R62H was lower than that of PITX2WT, and the mRNA levels of both β-catenin and CyclinD1 were higher than that of PITX2WT It is speculated that R62H mutation causes Wnt / β-catenin → PITX2 signaling pathway to change, which leads to abnormal gene expression, resulting in abnormal cell proliferation and corneal ring-like dermoid tumor formation.