Role of histone deacetylase CsHDA8 in regulating the accumulation of indole during the oolong tea manufacturing process

Aroma is an important quality-related trait of oolong tea.The compounds contributing to oolong tea aromas are mainly produced in response to stress during the enzyme-active stage of the tea manufacturing process.Epigenetic regulation affects stress-induced secondary metabolite production;however,the mechanisms regulating oolong tea aroma compound formation are unclear.In this study,the effect of histone acetylation on indole formation,an important aroma of oolong tea,was revealed and CsHDA8 was identified as a candidate regulator.Additionally,CsHDA8,which was localized in the nucleus and cytoplasm,may function as a histone deacetylase.Moreover,the binding of CsHDA8 to CsTSB2 promoter related to indole decreased during a wounding treatment,which resulted in increased histone acetylation and gene expression.The study results may clarify the regulatory effects of histone acetylation on the formation of tea secondary metabolites,with potential implications for studies on the epigenetic regulation in other non-model horticulture plants.