Sureshkumar Sridevi, Chhabra Aaryan, Guo Ya-Long, Balasubramanian Sureshkumar
School of Biological Sciences, Monash University, Clayton Campus, Melbourne, VIC, 3800, Australia.
State Key Laboratory of Plant Diversity and Speciality Crops/State Key Laboratory of Systematic and Evolutionary Botany, Institute of Botany, Chinese Academy of Sciences, Beijing, 100093, China.
New Phytol. 2025 Jul;247(2):504-517. doi: 10.1111/nph.70173. Epub 2025 May 5.
Repetitive DNA is a feature of all organisms, ranging from archaea and plants to humans. DNA repeats can be seen both in coding and in noncoding regions of the genome. Due to the recurring nature of the sequences, simple DNA repeats tend to be more prone to errors during replication and repair, resulting in variability in their unit length. This feature of simple sequence repeats led to their use as molecular markers for mapping traits in diverse organisms. Advances in genomics, and the ever-reducing costs of genome sequencing have empowered us to assess the functional impacts of DNA repeats. The variability in repeat lengths can cause phenotypic differences depending on where they are present in the genome. Variability in the repeat length in coding regions of genes results in poly amino acid stretches that appear to interfere with protein function, including the perturbation of protein-protein interactions with diverse phenotypic impacts. These are often common allelic variations that can significantly impact evolutionary dynamics. In extreme situations, repeats can undergo massive expansions and appear as outliers. Repeat expansions underlie several genetic defects in plants to diseases in humans. This review systematically analyses tandem DNA repeats in plants, their role in development and environmental response and adaptation in plants. We identify and synthesise emerging themes, differentiate repeat length variability and repeat expansions, and argue that many repeat-associated phenotypes in plants are yet to be discovered. We emphasise the underexplored nature and immense potential of this area of research, particularly in plants, and suggest ways in which this can be achieved and how it might contribute to evolution and agricultural productivity.
重复DNA是所有生物的一个特征，从古细菌、植物到人类均有。DNA重复序列在基因组的编码区和非编码区都能看到。由于序列的重复性，简单DNA重复序列在复制和修复过程中往往更容易出错，导致其单位长度出现变异性。简单序列重复的这一特征使其被用作多种生物性状定位的分子标记。基因组学的进展以及基因组测序成本的不断降低，使我们有能力评估DNA重复序列的功能影响。重复长度的变异性可能会导致表型差异，这取决于它们在基因组中的位置。基因编码区重复长度的变异性会导致多聚氨基酸序列的出现，并似乎会干扰蛋白质功能，包括扰乱蛋白质与蛋白质之间的相互作用，从而产生多种表型影响。这些通常是常见的等位基因变异，会对进化动态产生重大影响。在极端情况下，重复序列会发生大规模扩增并表现为异常值。重复序列的扩增是植物中多种遗传缺陷以及人类疾病的基础。本综述系统地分析了植物中的串联DNA重复序列、它们在植物发育、环境响应和适应中的作用。我们识别并综合了新出现的主题，区分了重复长度变异性和重复序列扩增，并认为植物中许多与重复序列相关的表型仍有待发现。我们强调了这一研究领域，特别是在植物方面，尚未得到充分探索的性质和巨大潜力，并提出了实现这一目标的方法以及它可能如何促进进化和农业生产力。
