Histone modification-dependent production of peptide hormones facilitates acquisition of pluripotency during leaf-to-callus transition in Arabidopsis

Chromatin configuration is critical for establishing tissue identity and changes substantially during tissue identity transitions; the leaf-to-callus transition is of particular interest because. the crucial scientific and agricultural technology of in-vitro tissue culture exploits callus formation from diverse tissue explants and tissue regeneration via de novo organogenesis. We analyzed changes in the global distribution of H3ac and H3K4me3 during the leaf-to-callus transition, with focus on open chromatin regions in calli relative to leaf explants, defined by increased accumulation of both H3ac and H3K4me3. Signaling peptides were identified as genes with accumulation of both H3ac and H3K4me3, and exogenous treatment of the identified peptide enhanced callus proliferation and de novo shoot regeneration. Chromatin immunoprecipitation DNA-sequencing (ChIP-seq) for histone modifications H3ac and H3K4me3 in mature leaf and callus cells.