XVI International Botanical Congess

Histone acetylation, which is controlled by an equilibrium between histone deacetylase (HD) and histone acetyltransferase (HAT), affects the chromatin structure and function. Homologues of HD gene (AtHD) and HAT gene (AtHAT) were isolated from Arabidopsis. On the basis of its deduced amino acid sequence comparison, these genes exhibited high homology to the genes isolated from yeast, human and Drosophila. Since the HD activity was involved in some external stimulation such as plant-pathogen interactions and ultraviolet irradiation, we investigated the effects of UV irradiation on the transcripts. The AtHD mRNA levels reduced within 30 min of UV irradiation in a dose-dependent manner and returned to the initial level after 32 hours.