Figure 4.

HDA18 Protein Binds and Affects Transcription of Certain Kinase Genes by Changing Their Histone Acetylation Status.

(A) ChIP-PCR verification of binding of HDA18 protein to putative targets identified by ChIP-chip. The genes marked with asterisks were false positives. The numbers listed to the right indicate the sites identified in the ChIP-chip analysis (for detailed information, see Supplemental Data Set 1 online).

(B) Expression levels of HDA18-targeted genes in root tips with altered HDA18 expression, showing upregulation of four kinase genes (highlighted with frames) regardless of increased or decreased expression of HDA18. Data show mean ± sd from three to four independent experiments, each with three replicates (*P < 0.05 and **P < 0.01; Student’s t test). Col, Columbia.

(C) and (D) Histone acetylation status of H3 and H4 correspond to altered HDA18 expression, examined by ChIP-PCR with AcH3 and AcH4 antibodies at the identified binding sites of selected kinase genes. Data show mean ± sd from five independent experiments, each with three replicates (*P < 0.05 and **P < 0.01; Student’s t test).