Generality and characteristics of genetic and epigenetic changes in newly synthesized allotetraploid wheat lines  

作　　者：Bao Qi 1,Xiaofang Zhong 1,Bo Zhu,Na Zhao,Liying Xu,Huakun Zhang,Xiaoming Yu,Bao Liu Key Laboratory of Molecular Epigenetics of MOE and Institute of Genetics & Cytology,Northeast Normal University,Changchun 130024,China 

出　　处：《Journal of Genetics and Genomics》2010年第11期737-748,共12页遗传学报（英文版）

基　　金：supported by the National Natural Science Foundation of China (No.30870178)

摘　　要：Previous studies have shown rapid and extensive genomic However, these studies are based on either a few pre-selected instability associated with early stages of allopolyploidization in wheat. genomic loci or genome-wide analysis of a single plant individual for a given cross combination, thus making the extent and generality of the changes uncertain. To further study the generality and characteristics of allopolyploidization-induced genomic instability in wheat, we investigated genetic and epigenetic changes from a genome-wide perspective （by using the AFLP and MSAP markers） in four sets of newly synthesized allotetraploid wheat lines with various genome constitutions, each containing three randomly chosen individual plants at the same generation. We document that although general chromosomal stability was characteristic of all four sets of allotetraploid wheat lines, genetic and epigenetic changes at the molecular level occurred in all these plants, with both kinds of changes classifiable into two distinct categories, i.e., stochastic and directed. The abundant type of genetic change is loss of parental bands while the prevalent cytosine methylation pattern alteration is hypermethylation at the CHG sites. Our results have extended previous studies regarding allopolyploidization-induced genomic dynamics in wheat by demonstrafing the generality of both genetic and epigenetic changes associated with multiple nascent allotetraploid wheat lines, and providing novel insights into the characteristics of the two kinds of induced genomic instabilities.Previous studies have shown rapid and extensive genomic However, these studies are based on either a few pre-selected instability associated with early stages of allopolyploidization in wheat. genomic loci or genome-wide analysis of a single plant individual for a given cross combination, thus making the extent and generality of the changes uncertain. To further study the generality and characteristics of allopolyploidization-induced genomic instability in wheat, we investigated genetic and epigenetic changes from a genome-wide perspective （by using the AFLP and MSAP markers） in four sets of newly synthesized allotetraploid wheat lines with various genome constitutions, each containing three randomly chosen individual plants at the same generation. We document that although general chromosomal stability was characteristic of all four sets of allotetraploid wheat lines, genetic and epigenetic changes at the molecular level occurred in all these plants, with both kinds of changes classifiable into two distinct categories, i.e., stochastic and directed. The abundant type of genetic change is loss of parental bands while the prevalent cytosine methylation pattern alteration is hypermethylation at the CHG sites. Our results have extended previous studies regarding allopolyploidization-induced genomic dynamics in wheat by demonstrafing the generality of both genetic and epigenetic changes associated with multiple nascent allotetraploid wheat lines, and providing novel insights into the characteristics of the two kinds of induced genomic instabilities.

关 键 词：ALLOPOLYPLOIDY genetic and epigenetic changes genome evolution tetraploid wheat 

分 类 号：S512.1[农业科学—作物学]