与人类某些疾病相关的线粒体RNA加工及其翻译机制

当今对线粒体基因的研究已越来越深入,它与人类的多种疾病有着密切关系.该文主要介绍与人类某些疾病有着直接联系的线粒体RNA加工及其翻译机制,尤其突出强调了导致各种疾病的调节因子,包括导致阿尔茨海默病、X连锁精神发育迟滞的线粒体RNA酶P蛋白2(mitochondrial RNaseP protein 2,MRPP2),极端肥胖的线粒体poly(A)聚合酶(mitochondrial poly(A)polymerase,MTPAP),非综合征母系遗传和抗生素致聋的h-mtTFB1,小儿脑病的EF - Tumt等.目前所取得的研究成果对治疗线粒体基础疾病具有重要的指导意义,但今后的研究仍然不能停止,并且应该加快对线粒体基因在体内如何差异性表达及其表达系统如何调控等方面研究的进程.     

Heterologous RNA replication enhancer stimulates in vitro RNA synthesis and template-switching by the carmovirus, but not by the tombusvirus, RNA-dependent RNA polymerase: implication for modular evolution of RNA viruses

The viral RNA plays multiple roles during replication of RNA viruses, serving as a template for complementary RNA synthesis and facilitating the assembly of the viral replicase complex. These roles are coordinated by cis-acting regulatory elements, such as promoters and replication enhancers (REN). To test if these RNA elements can be used by related viral RNA-dependent RNA polymerases (RdRp), we compared the potential stimulatory effects of homologous and heterologous REN elements on complementary RNA synthesis and template-switching by the tombus- (Cucumber necrosis virus, CNV), carmovirus (Turnip crinkle virus, TCV) and hepatitis C virus (HCV) RdRps in vitro. The CNV RdRp selectively utilized its cognate REN, while discriminating against the heterologous TCV REN. On the contrary, RNA synthesis by the TCV RdRp was stimulated by the TCV REN and the heterologous tombusvirus REN with comparable efficiency. The heterologous REN elements also promoted in vitro template-switching by the TCV and HCV RdRps. Based on these observations, we propose that REN elements could facilitate intervirus recombination and post-recombinational amplification of new recombinant viruses.