植物多倍体中的基因组印记

The genomic imprinting in ployploid plants

关键词:  多倍体  基因组印记  表观遗传

Key words:  polyploidy  genomic imprinting  epigenetic inheritance

摘要:

植物多倍体在自然界中广泛存在,这说明拥有多套遗传物质使得多倍体的适应进化具有优势。新多倍体形成后,一些基因组范围的变化较迅速地发生在多倍体形成开端,另一些在长期进化中发生。由于受到遗传、表观等因素的影响,亲本对于新形成多倍体基因组的贡献不均衡。这种偏向于某个亲本基因组的显性优势,称为基因组印记。植物多倍体中的基因组印记表现为基因组偏向性的序列消除、不均衡基因表达、基因沉默,这些受到基因组合并及DNA甲基化、核仁显性等表观因素影响。本文旨在为多倍体基因组进化及育种的相关研究提供参考。

Abstract:

Polyploidy is prevalent in nature, which reveals that there is an evolutionary advantage of having multiple sets of genetic materials for adaptive evolution in plants. When a new polyploid formed,many of genome-wide changes arose following the onset of polyploid formation,whereas others emerged on a longer evolutionary timescale. Owing to the influence of genetic and epigenetic mechanisms,the contributions of the parental genomes to the new formed polyploid were not equal. The dominance advantage of the biased parental genome was described as genomic imprinting. Genomic imprinting in polyploid plants showed the genome sequence of bias eliminating,imbalanced gene expression and gene silencing,which appeared to be caused by genome merger and epigenetic mechanisms: DNA methylation,nuclear dominance. This paper aimed to provide a reference for the research of genome evolution and polyploid breeding in plants.