Jiangsu Key Laboratory for Biodiversity and Biotechnology, College of Life Sciences, Nanjing Normal University, 1 Wenyuan Rd., Nanjing, 210023, China.
The Fourth Affiliated Hospital of China Medical University, Shenyang, 110032, China.
Sci Rep. 2022 Feb 10;12(1):2289. doi: 10.1038/s41598-022-06250-3.
The occurrence of gene duplication/amplification (GDA) provide potential material for adaptive evolution with environmental stress. Several molecular models have been proposed to explain GDA, recombination via short stretches of sequence similarity plays a crucial role. By screening genomes for such events, we propose a "SRS (short repeated sequence) N + unit + SRSN" amplified unit under USCE (unequal sister-chromatid exchange) for tandem amplification mediated by SRS with different repeat numbers in eukaryotes. The amplified units identified from 2131 well-organized amplification events that generate multi gene/element copy amplified with subsequent adaptive evolution in the respective species. Genomic data we analyzed showed dynamic changes among related species or subspecies or plants from different ecotypes/strains. This study clarifies the characteristics of variable copy number SRS on both sides of amplified unit under USCE mechanism, to explain well-organized gene tandem amplification under environmental stress mediated by SRS in all eukaryotes.
基因重复/扩增（GDA）的发生为适应环境压力的进化提供了潜在的物质。已经提出了几种分子模型来解释 GDA，序列相似性的短片段重组起着关键作用。通过对基因组进行此类事件的筛选，我们提出了一种在 USCE（不等姐妹染色单体交换）下的“SRS（短重复序列）N+单元+SRSN”串联扩增单元，用于通过具有不同重复数的 SRS 介导的串联扩增。在 2131 个精心组织的扩增事件中鉴定出的扩增单元，这些事件在各自的物种中产生了多基因/元件拷贝的扩增，随后进行了适应性进化。我们分析的基因组数据显示了相关物种或亚种之间或不同生态型/菌株的植物之间的动态变化。本研究阐明了 USCE 机制下扩增单元两侧可变拷贝数 SRS 的特征，以解释所有真核生物中由 SRS 介导的环境胁迫下的基因串联扩增的有序性。
