核仁显性与植物多倍体形成  

Nucleolar Dominance and Plant Polyploidy Formation

作　　者：陈纪鹏[1] 刘小林[1] 胡月清[1] 毛康康 CHEN Ji-peng;LIU Xiao-lin;HU Yue-qing;MAO Kang-kang(School of Life Science and Resource Environment Yichun University/Jiangxi Key Laboratory of Crop Growth and Development Regulation,Yichun 336000)

机构地区：[1]宜春学院生命科学与资源环境学院/江西省作物生长发育调控重点实验室,宜春336000

出　　处：《植物遗传资源学报》2023年第1期53-60,共8页Journal of Plant Genetic Resources

基　　金：国家自然科学基金(32060501);江西省重点研发计划(20212BBF63014);江西省自然科学基金(20202BABL205017)。

摘　　要：核仁显性在植物多倍化进程中发挥着重要作用,通过调节rDNA基因表达控制核糖体数量,使多倍体植物能够应对多倍化带来的遗传变化。串连重复的r DNA基因表达调控是一种大规模、整体基因表达调控模式,rDNA基因沉默往往发生在整个核仁组织区,受所处位置染色质状态控制,而不受基因前序列的影响。核仁显性不但在调控蛋白质合成中发挥着重要作用,还与多倍体染色体组稳定性相关,相应基因组的rDNA基因沉默往往引起该基因组的染色体消除,染色体消除也是多倍体形成过程中的一种应答机制。虽然大量证据表明核仁显性与染色体消除之间存在必然的联系,但rDNA基因表达稳定染色体的遗传机制仍不清晰,尤其是染色体消除的基因组特异性更难解释。因此,对核仁显性稳定染色体组的遗传机制进一步研究将揭示核仁在多倍体形成中的作用。本研究旨在阐述植物如何通过核仁显性应对多倍化带来的基因组冲击,呈现植物多倍化进程的一个侧面。Nucleolar dominance plays an important role in plant polyploidy. Polyploid can cope with the genetic changes in polyploidy via regulating the expression of rDNA genes to control the number of ribosomes.The rDNA gene expression regulation, which is controlled by the chromatin state rather than by the DNA sequence, is a large-scale and global pattern, and genes silencing usually occurs in the whole nucleolus region.Nucleolar dominance contributes to the protein synthesis and the genome stabilization. Chromosome elimination may be a way to response mechanism in polyploidy. Although the link between nucleolar dominance and chromosome elimination is supported by tremendous evidences, the genetic mechanism remains unclear, especially the genome specificity of chromosome elimination. Therefore, further research on the genetic mechanism will reveal the role of nucleolar dominance in the formation of polyploidy. The purpose of this study is to explain how plants cope with the genomic shock of polyploidy through nucleolar dominance, and to provide an insight in polyploidization.

关 键 词：核仁显性 多倍化 基因沉默 染色体消除 

分 类 号：Q943.2[生物学—植物学]