Involvement of histone acetylation in tomato resistance to Ralstonia solanacearum

Abstract Bacterial wilt (BW) is the most devastating vascular disease in tomato (Solanum lycopersicum L.), which caused by Ralstonia solanacearum (R. solanacearum). Although several strategies have been proposed to control BW, the molecular mechanisms are largely unknown. Here, we identify two tomato cultivars JG-No3 and XN021, which showed susceptible and resistant to R. solanacearum, respectively. Most defense-related genes were up-regulated in resistant cultivar XN021, whereas down-regulated in susceptible cultivar JG-No3. The expression of some histone deacetylases (HDACs) was reduced in XN021 compared to JG-No3. Furthermore, the disease symptoms were decreased in JG-No3 using the HDACs inhibitor, TSA (Trichostatin A) treatment. Silencing of SlHDA6, SlHDT1, SlHDT2, SlSRT1 and SlSRT2 using VIGS caused reducing disease incidence in susceptible cultivar JG-No3. In addition, histone H3 and H4 acetylation levels of defense-related genes were increased in both cultivars under R. solanacearum infection, especially XN021. Collectively, our results demonstrate that histone acetylation mediating by HDACs plays important roles in BW resistance in tomato. This study provides a new insight into the mechanism of disease response in BW.