Trinucleotide repeats are clustered in regulatory genes in Saccharomyces cerevisiae.
Trinucleotide repeats are clustered in regulatory genes in Saccharomyces cerevisiae.
复制标题
三核苷酸重复序列聚集在酿酒酵母的调控基因中。
DOI：
10.1093/genetics/154.3.1053
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发表时间：
2000
期刊：
影响因子：
3.3
通讯作者：
VanRiper,K
中科院分区：
文献类型：
--
作者：
Young,ET;Sloan,JS;VanRiper,K
酿酒酵母的基因组含有许多不稳定的微卫星序列。单核苷酸和二核苷酸重复很少在 ORF 中发现，当存在于 ORF 中时，它们经常位于内含子或蛋白质的 C 末端，表明它们的不稳定性对基因功能有害。在 ORF 中发现 DNA 三核苷酸重复 (TNR) 的频率高于预期，并且 TNR 编码的氨基酸代表了一组有偏差的氨基酸。 TNR 在具有相关序列的基因之间很少保守，表明高度不稳定或起源较新。 TNR 最常见的基因与细胞调节相关。蛋白质结构数据库明显缺乏含有氨基酸束的蛋白质，这表明它们不位于蛋白质的结构化区域，而是位于结构域之间。这一结论与两个蛋白质家族中氨基酸束的位置一致。 TNR 在与细胞调控相关的基因的 ORF 中的首选位置及其不稳定性表明 TNR 在物种形成中可能发挥重要作用。具体来说，TNR 可以作为重组的热点，导致结构域交换，或者 TNR 的突变可以允许蛋白质结构新结构域的快速进化。
The genome of Saccharomyces cerevisiae contains numerous unstable microsatellite sequences. Mononucleotide and dinucleotide repeats are rarely found in ORFs, and when present in an ORF are frequently located in an intron or at the C terminus of the protein, suggesting that their instability is deleterious to gene function. DNA trinucleotide repeats (TNRs) are found at a higher-than-expected frequency within ORFs, and the amino acids encoded by the TNRs represent a biased set. TNRs are rarely conserved between genes with related sequences, suggesting high instability or a recent origin. The genes in which TNRs are most frequently found are related to cellular regulation. The protein structural database is notably lacking in proteins containing amino acid tracts, suggesting that they are not located in structured regions of a protein but are rather located between domains. This conclusion is consistent with the location of amino acid tracts in two protein families. The preferred location of TNRs within the ORFs of genes related to cellular regulation together with their instability suggest that TNRs could have an important role in speciation. Specifically, TNRs could serve as hot spots for recombination leading to domain swapping, or mutation of TNRs could allow rapid evolution of new domains of protein structure.