eat can erase epigenetic marks of vernalization inArabidopsis

摘要

Vernalization establishes a memory ofwinter that must be maintained forweeks or months in order to promoteflowering the following spring. The sta-bility of the vernalized state varies amongplant species and depends on the dura-tion of cold exposure. InArabidopsisthaliana, winter leads to epigeneticsilencing of the floral repressor geneFLOWERING LOCUS C(FLC) and theduration of cold is measured through thedynamics of chromatin modificationsduring and after cold. The growing con-ditions encountered post-vernalizationare thus critical for the maintenance ofthe vernalized state. We reported thathigh temperature leads to devernalizationand, consistently, toFLCreactivation inArabidopsisseedlings. Here we show thatthe repressive epigenetic markH3K27me3 decreases at theFLClocuswhen vernalized seedlings are grown at30C, unless they were first exposed to astabilizing period at 20C. Ambient tem-perature thus controls the epigeneticmemory of winter.