2011-08-012024-05-17https://scholars.lib.ntu.edu.tw/handle/123456789/682789Abstract: Epigenetic mechanisms such as histone modifications have a decisive function in regulating plant responses to abiotic stresses. Among the multiple epigenetic mechanisms that modify chromatin to regulate gene expression, histone modifications including acetylation and methylation play a major role. Histone acetylation levels are determined by the action of histone acetyltransferases and histone deacetylases, whereas histone methylation is dynamically regulated by histone methyltransferases and demethylases. There are two types of histone demethylases with distinct mechanisms, amine oxidation by lysine-specific demethylase1 (LSD1) and hydroxylation by Jumonji C (JmjC) domain-containing proteins, removing methyl groups from methylated lysine residues. In our previously work we demonstrated that histone acetylation and methylation is involved in plant stress responses. Our more recent studies indicate that histone deacetylase HDA6 and histone demethylase FLD can crosstalk mediated by physical association. The proposal research addresses the functional significance of histone demethylases and their interaction with histone deacetylases. T-DNA insertion mutants and overexpression plants will be used to determine the roles of histone demethyleses in abiotic stress response. DNA microarray, chromatin immunoprecipitation (ChIP) and ChIP sequencing will be applied to identify the genes regulated by histone demethylases. Using genetic and molecular approaches, we will reveal the function of histone demethylases in plant stress responses. Such analysis will provide insights into the epigenetic mechanisms of plant response to environmental stresses. Given the importance of histone modifications in regulation of gene expression in plants, a better understanding of how histone modifications modulate gene expression in plant stress response may have wide application in crop improvement.