Department of Biology, Texas A & M University, College Station, TX 77843, USA.
Genetics Interdisciplinary Program, Texas A & M University, College Station, TX 77843, USA.
Genes (Basel). 2020 Aug 16;11(8):945. doi: 10.3390/genes11080945.
Microsatellites are short, repetitive DNA sequences that can rapidly expand and contract due to slippage during DNA replication. Despite their impacts on transcription, genome structure, and disease, relatively little is known about the evolutionary dynamics of these short sequences across long evolutionary periods. To address this gap in our knowledge, we performed comparative analyses of 304 available insect genomes. We investigated the impact of sequence assembly methods and assembly quality on the inference of microsatellite content, and we explored the influence of chromosome type and number on the tempo and mode of microsatellite evolution across one of the most speciose clades on the planet. Diploid chromosome number had no impact on the rate of microsatellite evolution or the amount of microsatellite content in genomes. We found that centromere type (holocentric or monocentric) is not associated with a difference in the amount of microsatellite content; however, in those species with monocentric chromosomes, microsatellite content tends to evolve faster than in species with holocentric chromosomes.
微卫星是短的、重复的 DNA 序列，由于 DNA 复制时的滑动，它们可以迅速扩张和收缩。尽管这些短序列对转录、基因组结构和疾病有影响，但对于这些短序列在长进化时期的进化动态，我们知之甚少。为了填补我们知识上的这一空白，我们对 304 个可用的昆虫基因组进行了比较分析。我们研究了序列组装方法和组装质量对微卫星含量推断的影响，探索了染色体类型和数量对地球上最具物种多样性的一个类群的微卫星进化速度和模式的影响。二倍体染色体数量对微卫星进化的速度或基因组中微卫星含量没有影响。我们发现着丝粒类型（全着丝粒或单着丝粒）与微卫星含量的差异无关；然而，在那些具有单着丝粒染色体的物种中，微卫星含量的进化速度往往比具有全着丝粒染色体的物种快。
