Heritable Alterations In DNA Methylation Pattern And Mobilization Of Transposon Induced By Laser Irradiation In Jijing88

Epigenetic inheritance modification of organisms can be response to endogenous stress and exogenous stress.Including genome range of genetic variation and apparent genetic variation,genetic variations mainly through the change of gene expression in the phenotype and displays the change of apparent genetic variation, mainly manifested in DNA methylation cytosine and histone acetylation and siRNA change such as the regulation of gene expression and genome stability. Laser irradiation is one source of abiotic stress of exogenous stress, can be caused plant stress response and epigenetic variation.DNA methylation as an important epigenetic modification plays an important role in controlling gene expression and maintaining genomic stability in animals and plants. Many studies have shown that there is connection between DNA methylation and transposon activity. Identification of specific inducible conditions whereby certain dormant elements can be activated to transpose is important to further understand the biological roles of mobile elements.Recently,the miniature Ping was isolated active MITE mobile elements from rice generation,which was mobilized byγ-ray irradiation and tissue culture in abiotic stress.The laboratory uses semiconductor-pumped all-solid-state laser,He-Ne laser-irradiated and Nd3+YAG(IR) laser-irradiated,three different laser irradiation to treat genotypes of rice Jijing 88 embryos,analysis to rice production of the phenotypic variation and variation of DNA methylation and mobilization of mPing by locus-specific PCR are:after laser treatment, plants in the field appear to dwarf plant height, delayed heading, tiller and less phenotypic variation; to find out laser treatment lead to epigenetic variation of Jijing88 MO generation genome DNA methylation changes;and induce the activation of mPing in MO generation of mutiple sites.To further study to find out if laser treatment may lead to epigenetic variation of Jijing 88 generations, this study analysis of semiconductor-pumped all-solid-state laser irradiating influence epigenetic variation-DNA methylation.alterations in Jijing88 M1 generation. The main results are:(1)To find out laser irradiation lead to dwarf plant height,delayed heading of phenotypic variatio in M1 generation of Jijing 88.(2)MSAP analysis of laser treatment shows:genome-wide demethylation variation in M1 generation of plant. Methylation of genetic variation of MO is inherited to the Ml generation through meiosis. (3) In the analysis of PCR of mPing sites in Ml generation, it appears mPing activation in multiple genomic sites and it inherits transposition mPing activated in MO generation, the highest jump frequency is 60%.Southern Blot:results showed that caused Jijing88 mobilization of several previously characterized transposable elements, including a MITE (mPing) and its putative transposase-encoding partner Ping.Based on the above findings, it is concluded that Laser irradiation can induce epigenetic variation and induce endogenous rice genome transposon activation in high frequency and therefore can cause methylation variation. Thus, this study can provide a new basis for mutation breeding of crops.