Histone deacetylases are known to play a crucial role in regulating histone post-translational modifications, we then decided to check the occupancy of HDAC1, the enzyme that catalyses deacetylation reaction, at the promoter regions of the defense genes at 6 and 24 h post-infection using ChIP assay with HDAC1-specific antibody. The gene discussed is HDAC1; the disease is infection.