Institute of Research and Development, Duy Tan University, Da Nang, 550000, Viet Nam; Division of Biological Sciences, University of Missouri, Columbia, MO, 65211, USA.
Department of Electrical Engineering and Computer Science, University of Missouri, Columbia, MO, 65211, USA.
J Genet Genomics. 2020 Feb 20;47(2):93-103. doi: 10.1016/j.jgg.2020.02.002. Epub 2020 Feb 19.
Aneuploidy has profound effects on an organism, typically more so than polyploidy, and the basis of this contrast is not fully understood. A dosage series of the maize long arm of chromosome 1 (1L) was used to compare relative global gene expression in different types and degrees of aneuploidy to gain insights into how the magnitude of genomic imbalance as well as hypoploidy affects global gene expression. While previously available methods require a selective examination of specific genes, RNA sequencing provides a whole-genome view of gene expression in aneuploids. Most studies of global aneuploidy effects have concentrated on individual types of aneuploids because multiple dose aneuploidies of the same genomic region are difficult to produce in most model genetic organisms. The genetic toolkit of maize allows the examination of multiple ploidies and 1-4 doses of chromosome arms. Thus, a detailed examination of expression changes both on the varied chromosome arms and elsewhere in the genome is possible, in both hypoploids and hyperploids, compared with euploid controls. Previous studies observed the inverse trans effect, in which genes not varied in DNA dosage were expressed in a negative relationship to the varied chromosomal region. This response was also the major type of changes found globally in this study. Many genes varied in dosage showed proportional expression changes, though some were seen to be partly or fully dosage compensated. It was also found that the effects of aneuploidy were progressive, with more severe aneuploids producing effects of greater magnitude.
非整倍体对生物体有深远的影响，通常比多倍体更为显著，而这种对比的基础尚未完全理解。本研究利用玉米 1 号染色体长臂（1L）的剂量系列，比较不同类型和程度的非整倍体中相对的全局基因表达，以深入了解基因组失衡的幅度以及低倍体如何影响全局基因表达。虽然以前的方法需要选择性地检查特定的基因，但 RNA 测序提供了非整倍体中基因表达的全基因组视图。大多数关于全局非整倍体效应的研究都集中在个别类型的非整倍体上，因为在大多数模型遗传生物体中很难产生相同基因组区域的多个剂量非整倍体。玉米的遗传工具包允许检查多个倍性和 1-4 个染色体臂的剂量。因此，与整倍体对照相比，可以在低倍体和高倍体中详细检查变化的染色体臂和基因组其他部位的表达变化。以前的研究观察到反转(trans)效应，即 DNA 剂量没有变化的基因与变化的染色体区域呈负相关表达。这种反应也是本研究中全局变化的主要类型。虽然有些基因被部分或完全补偿，但许多基因的剂量变化表现出比例表达变化。研究还发现，非整倍体的影响是渐进的，更严重的非整倍体产生更大幅度的影响。
