端粒酶及靶向端粒酶抗衰老和肿瘤药物的研究进展

端粒是由重复性DNA序列和特殊蛋白质组成的真核染色体末端的保护性结构。由于末端复制问题,端粒在细胞复制增殖过程中逐渐缩短,而过短的端粒导致基因组不稳定,引起细胞衰老和机体老化。端粒酶是具有催化端粒DNA合成能力的逆转录酶,能够维持细胞内端粒的长度或延缓细胞增殖过程中端粒的缩短。因此,端粒酶和机体衰老及端粒相关疾病具有重要的因果关系,被认为是抗衰老和癌症的潜在靶点。本文对端粒酶的结构、活性调控及基于端粒酶治疗的研究进展进行综述,为端粒酶相关领域的研究以及开发以端粒酶为靶点的药物提供参考。

Hepatitis C virus nonstructural protein NS_3 and telomerase activity

OBJECTIVE: To study the effect of hepatitis C virus nonstructural protein NS(3) (HCV NS3) on telomerase activity and carcinogenesis. METHODS: Streptavidin-peroxidase (SP) conjugated method was used to detect the expression of HCV NS(3) protein in NIH3T3 cells transfected with plasmid pRcHCNS(3)-5' and pRcHCNS(3)-3'. Telomerase activity was detected by an in situ telomerase activity labeling method, telomeric repeat amplification protocol polymerase chain reaction (TRAP-PCR) and telomerase PCR enzyme linked immunosorbent assay (ELISA) technology in the transfected and non-transfected NIH3T3 cells. RESULTS: HCV NS(3) protein was expressed in the NIH3T3 cells transfected with plasmid pRcHCNS(3)-5' expressing HCV NS(3) C-terminal deleted protein or with plasmid pRcHCNS(3)-3' expressing HCV NS(3) N-terminal deleted protein. The positive signal of HCV NS(3) protein was localized in the cytoplasm of NIH3T3 cells, and the signal intensity of the former was stronger. Telomerase activity in NIH3T3 cells transfected with plasmid pRcHCNS(3)-5' was stronger than that in NIH3T3 cells transfected with plasmid pRcHCNS(3)-3' (P

Hepatitis C virus nonstructural protein NS3 and telomerase activity

To study the effect of hepatitis C virus nonstructural protein NS 3 (HCV NS3) on telomerase activity and carcinogenesis Methods Streptavidin peroxidase (SP) conjugated method was used to detect the expressio n of HCV NS 3 protein in NIH3T3 cells transfected with plasmid pRcHCNS 3 5’ and pRcHCNS 3 3’ Telomerase activity was detected by an in situ telomerase a ctivity labeling method, telomeric repeat amplification protocol polymerase chai n reaction (TRAP PCR) and telomerase PCR enzyme linked immunosorbent assay (ELI SA) technology in the transfected and non transfected NIH3T3 cells Results HCV NS 3 protein was expressed in the NIH3T3 cells transfected with plasmid pR cHCNS 3 5’ expressing HCV NS 3 C terminal deleted protein or with plasmid pR cHCNS 3 3’ expressing HCV NS 3 N terminal deleted protein The positive sig nal of HCV NS 3 protein was localized in the cytoplasm of NIH3T3 cells, and th e signal intensity of the former was stronger Telomerase activity in NIH3T3 c ells transfected with plasmid pRcHCNS 3 5’ was stronger than that in NIH3T3 c ells transfected with plasmid pRcHCNS 3 3’ ( P 【0 01), whereas telomerase a ctivity in NIH3T3 cells transfected with plasmid pRcCMV or untreated NIH3T3 ce lls was weaker than that in NIH3T3 cells transfected with plasmid pRcHCNS 3 3 ’ ( P 【0 05) The expression level of HCV NS 3 protein was significantly co rrelated with the strength of telomerase activity ( P 【0 05) The results ob tained by in situ telomerase activity labeling corresponded to the results by te lomerase PCR ELISA technology Conclusions HCV NS 3 protein may activate telomerase through endogenous mechanism to induce host cell transformation The effect of HCV NS 3 C terminal deleted protein on telomerase activity in the host cell may be stronger than that of HCV NS 3 N terminal deleted protein In situ telomerase activity labeling was a reliabl e technology for studying pathological morphology and telomerase activity in tis sues and cells