Spatial-temporal Expression Pattern Analasis Of Dna Methylation Regulation Gnens In Arabidopsis

DNA methylation regulation plays important roles in transposable elements controlling, chromatin structure shaping and gene expression regulation in plant. The research in the past two decades of A. thaliana DNA methylation regulation are mainly focus on uncovering components controlling the methylation level of the genome. Until now, the main genes in A. thaliana DNA methylation regulation network are supposed to be found. However, the important function of DNA methylation regulation in plant development is rarely know. In this paper, we systematically surveyed the transcription profile of these already found A. thaliana DNA methylation regulation genes, and investigated their roles in A. thaliana development.Spatio-temporal expression profile analysis of A. thaliana DNA methylation regulation genes(ADMR genes) shows that they are preferred expressing in reproductive tissues than in vegetable tissues. And they are particularly high expressing in tissues which are under vigorous differentiation, especially the shoot apex meristem and developing embryo. ADMR genes go through an expression peak during the formation of flower primordium, but would reduce dramatically after the flower primordium was formed. And after the flower stage 12, the expression of ADMR genes in flower organ are focus in carpels, in which the female gametes is generating. ADMR genes also highly express during embryo development, especially in 6th and 7th day after fertilization.Notably, we found that the ADMR genes including RdDM pathway genes and its antagonistic demethylation pathway genes as well as methylation maintenance pathway genes are synchronously active expressed during floral and embryo development. Moreover, during the asymmetrical cell division event in the progress of pollen genesis, the ADMR genes high express before the asymmetrical division, but would reduce dramatically after the asymmetrical division was finished. We also found that in ddm1 mutant(decrease of DNA methylation 1), the chromatin is decondensed. These results indicate that ADMR genes are required for cell differentiation and this may be one of the reasons why they are high expressed in reproductive development.In conclusion, DNA methylation regulation genes are high expressed in A. thaliana reproductive development. And reason for this may be that DNA methylation reprograming is required for cell differentiation in reproductive development process.