细菌Ⅱ组内含子（GroupⅡintron）的转移机制

Mobility of Bacterial Group Ⅱ Introns - A review

摘要:

摘要: 约14年前在真核生物中发现的Ⅱ组内含子不仅具有催化功能，而且是可移动的逆转录元件。近年来研究发现细菌中也有可移动的Ⅱ组内含子，它们能够逆转录归巢进入同源无内含子的等位基因位点或者逆转录转座进入非等位基因位点。本文试图从细菌Ⅱ组内含子编码蛋白的活性功能域的组成与Ⅱ组内含子转移发生途径之间的联系，综述已知细菌Ⅱ组内含子主要的移动机制。同时，依据作者多年来研究海洋蓝细菌Ⅱ组内含子编码蛋白对Ⅱ组内含子剪接机理的结果，探讨了海洋蓝细菌Ⅱ组内含子是否会发生转移以及可能的转移方式，探讨了Ⅱ组内含子在生物基因组中发生转移的生物学意义。

Abstract:

Abstract: Group II introns are both catalytic RNAs (ribozymes) and mobile retroelements that were discovered about 14 years ago. Mobile Group II introns were also found in bacteria recently, and they can either retrohome into cognate alleles that lack the intron or retrotranspose to ectopic sites. We reviewed the main mobility (homing) pathways of bacterial group II introns by describing the relationship between Intron-encoded protein activities and intron mobility. We discussed whether mobility of Cyanobacteria group Ⅱ introns could occur and possible mechanisms of their mobility. Furthermore, the biological implications of groupⅡ introns transferring within a species or among different species are also discussed.