Turmel M, Choquet Y, Goldschmidt-Clermont M, Rochaix J D, Otis C, Lemieux C
Département de biochimie, Faculté des sciences et de génie, Université Laval, Québec, Canada.
Curr Genet. 1995 Feb;27(3):270-9. doi: 10.1007/BF00326160.
In the secondary structure model that has been proposed for the trans-spliced intron 1 in the Chlamydomonas reinhardtii psaA gene, a third RNA species (tscA RNA) interacts with the 5' and 3' intron parts flanking the exons to reconstitute a composite structure with several features of group-II introns. To test the validity of this model, we undertook the sequencing and modelling of equivalent introns in the psaA gene from other unicellular green algae belonging to the highly diversified genus Chlamydomonas. Our comparative analysis supports the model reported for the C. reinhardtii psaA intron 1, and also indicates that the 5' end of the tscA RNA and the region downstream from the psaA exon 1 cannot be folded into a structure typical of domain I as described for most group-II introns. It is possible that a fourth RNA species, yet to be discovered, provides the parts of domain I which are apparently missing.
在莱茵衣藻psaA基因中为反式剪接内含子1所提出的二级结构模型中，第三种RNA分子（tscA RNA）与外显子两侧的5'和3'内含子部分相互作用，以重建具有II类内含子若干特征的复合结构。为了验证该模型的有效性，我们对来自高度多样化的衣藻属的其他单细胞绿藻的psaA基因中的等效内含子进行了测序和建模。我们的比较分析支持了关于莱茵衣藻psaA内含子1的报道模型，并且还表明tscA RNA的5'端和psaA外显子1下游的区域不能折叠成如大多数II类内含子所描述的典型结构域I的结构。有可能尚未发现的第四种RNA分子提供了明显缺失的结构域I的部分。
