Chromatin Immunoprecipitation (ChIP) Assay

ChIP assays were performed as previously described [31 (link)]. Generally, seeds were collected and fixed with 1% formaldehyde. The chromatin was isolated and sonicated to generate DNA fragments with an average size between 300–500bp. Then solubilized chromatin was immunoprecipitated using Protein G Dynabeads (Thermo) and incubated with antibodies [anti-ABI5 (Abcam), anti-GFP (Invitrogen), anti-H3Ac (EMD Millipore), anti-H3K9Ac (EMD Millipore), anti-H3K14Ac (EMD Millipore), anti-H3K18Ac (EMD Millipore) and H3K27Ac (EMD Millipore)]. The co- immunoprecipitated DNA was recovered and analyzed by real-time PCR. All ChIP-qPCR primers used in this paper are listed in Supplemental Table. S1.