Abstract
Epigenetic regulations, including histone modifications, are crucial for the maintenance of cell states. Reprogramming from differentiated cells to pluripotent stem cells is a cell state change. In this study, the state change from a leaf cell to a protonemal apical cell of Physcomitrella was used as a model system for reprogramming. Epigenome studies for histone modifications were conducted by chromatin immunoprecipitation followed by sequencing (ChIP-seq) using a next-generation sequencer. Among several types of histone modification, the trimethylation of Lys4 (K4) and Lys27 (K27) of histone 3 (H3) were selected for ChIP-seq analysis representing active and inactive chromatin marks, respectively. Nucleosome occupancy was also surveyed with the pan-histone 3 antibody. So far, a set of ChIP-seq data for leafy gametophores (differentiated sample), protoplast derived from the protonema-apical cells (stem cell sample) and dissected gametophores (reprogramming samples) have been obtained. Integrated analysis of ChIP-seq and gene expression will produce useful information for epigenetics-based regulation of the reprogramming process.
