Fontaine J M, Goux D, Kloareg B, Loiseaux-de Goër S
Centre d'Etudes d'Océanographie et de Biologie Marine, Station Biologique de Roscoff, CNRS (UPR 9042), UPMC, BP 74, 29682 Roscoff Cedex, France.
J Mol Evol. 1997 Jan;44(1):33-42. doi: 10.1007/pl00006119.
The mitochondrial genome of the brown alga Pylaiella littoralis contains two different types of group II introns. They each encode complete complex proteins, i.e., with a reverse transcriptase domain, a maturase or X domain, and an endonuclease or H-N-H/zinc finger domain. To our knowledge, this is the first example of the presence in the same genome of introns belonging to subgroups IIA and IIB which both contain multidomained RT-like proteins. We describe the group IIA introns that interrupt the cox1 gene. The RT-like proteins contained in these introns were compared to those of the LSU rDNA group IIB introns. The phylogenetic relationships of these intron ORFs were investigated and the possible evolution of group II introns is discussed.
褐藻小海带的线粒体基因组包含两种不同类型的II类内含子。它们各自编码完整的复合蛋白，即具有逆转录酶结构域、成熟酶或X结构域以及内切核酸酶或H-N-H/锌指结构域。据我们所知，这是同一基因组中同时存在属于IIA和IIB亚组的内含子的首个例子，这两个亚组都含有多结构域的类逆转录酶蛋白。我们描述了中断cox1基因的IIA类内含子。将这些内含子中包含的类逆转录酶蛋白与LSU rDNA的IIB类内含子中的蛋白进行了比较。研究了这些内含子开放阅读框的系统发育关系，并讨论了II类内含子可能的进化情况。
