Carpousis A J, Vanzo N F, Raynal L C
Laboratoire de Microbiologie et Génétique Moléculaíre, Centre National de la Recherche Scientifique, Toulouse, France.
Trends Genet. 1999 Jan;15(1):24-8. doi: 10.1016/s0168-9525(98)01627-8.
The Escherichia coli RNA degradosome is a multiprotein complex containing an endoribonuclease, polynucleotide phosphorylase and a DEAD-box RNA helicase. A related complex has been described in the spinach chloroplast. The exosome and the mtEXO complex have recently been described in yeast and it is likely that related complexes also exist in animal cells. This research suggests the widespread existence of sophisticated machines for the efficient degradation of messenger RNA. The DEAD-box helicase in the degradosome can unwind regions of RNA structure that interfere with 3'-5' degradation. The polyadenylation of RNA 3' ends is also known to promote degradation by creating a 'toehold' for the degradation machinery. Much remains to be learned about the regulation of mRNA stability. The complexity of the degradation process, both in the eubacteria and in the eukaryotes, suggests that many steps are possible points of control.
大肠杆菌RNA降解体是一种多蛋白复合体，包含一种核糖核酸内切酶、多核苷酸磷酸化酶和一种DEAD盒RNA解旋酶。菠菜叶绿体中也描述了一种相关复合体。最近在酵母中发现了外切体和线粒体EXO复合体，动物细胞中可能也存在相关复合体。这项研究表明，存在用于高效降解信使RNA的复杂机制的现象很普遍。降解体中的DEAD盒解旋酶可以解开干扰3'-5'降解的RNA结构区域。已知RNA 3'末端的多聚腺苷酸化也通过为降解机制创造一个“支点”来促进降解。关于mRNA稳定性的调控仍有许多有待了解的地方。真细菌和真核生物中降解过程的复杂性表明，许多步骤都可能是控制点。
