Histone deacetylase gene SlHDA1 regulates drought and salt tolerance in tomato (Solanum lycopersicum)

Abstract

Histone deacetylase (HDACs) genes perform as crucial regulators widely participation in the process of plant growth development and ripening in plants. Nevertheless, the detailed functions for most Histone deacetylase (HDACs) members in tomato remain unknown. Here we isolated and identified the functional characterization of SlHDA1 under salt and drought stresses in tomato. Silencing of SlHDA1 in tomato, the expression of ABA signal transduction- and biosynthesis-related genes were reduced in transgenic plants compared with WT. The results of stress tolerance assays showed that reduced tolerance to drought and salt stresses were demonstrated in SlHDA1-RNAi transgenic plants compared with WT plants. In accordance with the results of a series of physiological parameters related to stress response including decreased ABA, Pro, chlorophyll contents and CAT activity, and increased MDA content. Besides, the results of RNA-seq analysis showed that the transcription level of abiotic stress- and biotic stress-related genes which encoding defense proteins were down-regulated in SlHDA1-RNAi transgenic plants, such as stress-related gene SlABCC10 and the voltage-dependent anion channel-related gene SlAH3 and pathogenesis-related proteins P450 genes SlCYP71A1, SlCYP736A12, SlCYP94A2 and ABA biosynthesis-related genes SlCYP707A4, suggesting that SlHDA1 acts as an important role in the mediating the genes associated with biotic and abiotic stress response. Taken together, the data reveal that SlHDA1 plays an indispensable role in drought and salt stress tolerance by controlling the pathway of ABA-mediated, and have promising applications in the drought- and salt- tolerance tomato cultivars engineering.