Multiscale chromatin dynamics and high entropy in plant iPSC ancestors

Abstract

Protoplasts, derived from plant tissues, are considered functional equivalent of animal induced pluripotent stem cells (iPSC). Similarly, to their animal counterparts, plant iPSC show large-scale, chromatin reorganisation, thought to be a hallmark of pluripotency acquisition. To capture in more details the nuclear morphology and chromatin organisation of plant iPSC, we deployed high- throughput imaging and a custom, supervised image analysis protocol extracting over 100 chromatin features. Our study unravels a rapid, multiscale dynamics of chromatin patterns which trajectory strongly depends on nutrients availability. We measured a high heterogeneity of chromatin features indicating an intrinsic entropy of iPSC cultures, which reduced over time. We found that entropy reduction is antagonistically controlled by phytohormones and intrinsic epigenetic factors.