Regulation of Peanut Stress Response by Histone Acetylation: Insights from HATs and HDACs

Histone acetylation is a key epigenetic mechanism regulating plant stress responses. In this study, 35 histone acetyltransferases (AhHATs) and 39 histone deacetylases (AhHDACs) were identified in peanut (Arachis hypogaea L.). Phylogenetic analysis revealed conserved groups, and promoter analysis highlighted stress-responsive cis-elements. Expression profiling demonstrated tissue-specific patterns and differential regulation under drought and salt stress. Inhibition of HDAC activity using trichostatin A (TSA) reduced stress tolerance and diminished antioxidant enzyme activities. Silencing of AhHDAC30 enhanced histone acetylation at the AhPOD promoter, upregulating its expression and improving stress resistance. Transgenic Arabidopsis overexpressing AhHDAC30 exhibited enhanced salt tolerance. These findings illustrate the critical roles of histone acetylation in mediating stress responses and antioxidant regulation in peanut and highlight candidate genes for breeding stress-resistant varieties.