全长新基因PPIL3的获得及在人脑胶质瘤中的表达

Isolation and expression of one novel full-length gene related to human glioma

目的运用基因芯片技术获取正常成人脑组织与人脑胶质瘤中差异表达的基因，并对其中1条基因进行初步研究。方法抽提正常成人脑组织与人脑胶质瘤组织中的mRNA来制备探针，经杂交、洗涤后，通过计算机观察两者表达谱的差异情况，对681F05克隆子进行Northern blot，原位杂交和生物信息学分析。结果通过4次基因芯片筛选，获得15条与胶质瘤相关的新基因，经northern blot证实681F05基因在人正常脑组织中低表达，而在人脑胶质瘤中高表达。原位杂交得到相同的结果。BLASTn和BLASTx分析显示，它们编码蛋白与线虫Cyp-10蛋白同源性分别为52％和72％。cDNA序列分析发现这两上克隆是同一个基因（命名为cyclophilin—like gene（PHL3））的两个不同的剪切体（PPIL3a和PPIL3b）。结论基因芯片筛选正常脑组织与人脑胶质瘤差异表达的基因具有样品用量少，高质量，高速度，高敏感等特性。681F05基因可能是与人脑胶质瘤形成有关的一条全长新基因。

Objective To obtain differentially expressed genes related to human glioma using cDNA microarray and the characterization of one novel full-length gene. Methods Total RNA was extracted from human glioma tissues and normal brain tissues, and mRNA was used to make probes. After hybridization and washing procedures, the results of hybridization were scanned using computer system. One gene named 681 F05 clone was subsequently analyzed by northern blot ,in situ hybridization and bioinformatics. Results Fifteen differentially expressed genes to human glioma were obtained through four times hybridizations and scanning. Northern blot analysis confirmed 681F05 clone was low-expressed in human brain tissue and over-expressed in human glioma tissues. This result was just the same as the result of in situ hybridization. The analysis of BLASTn and BLASTx showed that clone 681F05 we isolated was two cDNA clones encoding two novel proteins which showed 52% and 72% identity to the cyclophilin isoform 10 of C. Elgans, respectively. Sequence analysis revealed these two cDNA clones were two different splicing variants of a novel cycophilin-like gene （ PPIL3a and PPIL3b）. Conclusion cDNA microarray technology can be successfully applied to identify differentially expressed genes. The novel full-length gene of human PPIL3 may be correlated with the genesis of human glioma.