Group I intron lateral transfer between red and brown algal ribosomal RNA
Group I intron lateral transfer between red and brown algal ribosomal RNA
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DOI：
10.1007/s002940100227
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发表时间：
2001-08-01
期刊：
影响因子：
2.5
通讯作者：
Gutell, RR
中科院分区：
文献类型：
--
作者：
Bhattacharya, D;Cannone, JJ;Gutell, RR
I族内含子如何起源于核糖体RNA基因是进化生物学中的一个重要问题。这个问题的核心是在进化上亲缘关系较远的植物、真菌和原生生物谱系中存在的大量I族内含子，以及对它们的起源和从一个外显子到另一个外显子、细胞器之间和细胞之间的横向转移的理解。这些内含子的一级和二级结构差异很大；它们的来源是一些或可能是许多在rnas中传播的可移动元素，这是未知的。在这里，我们展示了一个新的谱系，插入在小亚基rRNA中的516位（大肠杆菌基因编号）的ICl组内含子在bangiophyte红藻和褐藻（Aureoumbra lagunensis）中是特异性相关的，尽管它们的宿主细胞不是。这些斑状和金黄色内含子是已知的唯一在P5b螺旋中有螺旋插入的情况。额外的P5b - ix的一级和二级结构高度保守，这表明它很重要，尽管其具体功能尚不清楚。我们的研究试图了解这些ICl内含子的起源和运动。
How group I introns originate in nuclear ribosomal (r)RNA genes is an important question in evolutionary biology. Central to this issue is the multitude of group I introns present in evolutionarily distantly related plant, fungal, and protist lineages, together with an understanding of their origin and lateral transfer from one exon to another, between cell organelles, and between cells. These introns vary considerably in primary and secondary structure; and their provenance from a few or perhaps many mobile elements that have spread in rRNAs is unknown. Here we show that a novel lineage of group ICl introns inserted at position 516 (Escherichia coli gene numbering) in the small subunit rRNA in bangiophyte red algae and a brown alga (Aureoumbra lagunensis) are specifically related, although their host cells are not. These bangiophyte and Aureoumbra introns are the only known cases that have a helical insertion in the P5b helix. The highly conserved primary and secondary structure of the extra P5b he ix suggests that it is important, although its specific function is unknown. Our study attempts to understand the origin and movement of these ICl introns.