INRA, Micalis UMR 1319, Biologie Intégrative du Métabolisme Lipidique Microbien, Bâtiment CBAI, 78850 Thiverval-Grignon, France.
C R Biol. 2011 Aug-Sep;334(8-9):662-70. doi: 10.1016/j.crvi.2011.05.015. Epub 2011 Jul 6.
Whatever their abundance in genomes, spliceosomal introns are the signature of eukaryotic genes. The sequence of Saccharomyces cerevisiae, achieved fifteen years ago, revealed that this yeast has very few introns, but conserved intron boundaries typical for an intron definition mechanism. With the improvement and the development of new sequencing technologies, yeast genomes have been extensively sequenced during the last decade. We took advantage of this plethora of data to compile and assess the intron content of the protein-coding genes of 13 genomes representative of the evolution of hemiascomycetous yeasts. We first observed that intron paucity is a general rule and that the fastest evolving genomes tend to lose their introns more rapidly (e.g. S. cerevisiae versus Yarrowia lipolytica). Noticeable differences were also confirmed for 5' splice sites and branch point sites (BP) as well as for the relative position of the BP. These changes seemed to be correlated with the lineage specific evolution of splicing factors.
无论在基因组中多么丰富，剪接体内含子都是真核基因的特征。十五年前完成的酿酒酵母序列表明，这种酵母的内含子非常少，但具有典型的内含子定义机制的保守内含子边界。随着测序技术的改进和发展，在过去十年中，酵母基因组得到了广泛的测序。我们利用这些大量的数据，编译和评估了代表半子囊菌酵母进化的 13 个基因组的蛋白质编码基因的内含子含量。我们首先观察到内含子的缺乏是普遍规律，并且进化最快的基因组往往更快地失去它们的内含子（例如，酿酒酵母与解脂耶氏酵母）。5' 剪接位点和分支点（BP）以及 BP 的相对位置也得到了明显的证实。这些变化似乎与剪接因子的谱系特异性进化有关。
