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Vernalization and epigenetics: how plants remember winter.

Sibum Sung·Richard M Amasino
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Abstract

One of the remarkable aspects of the promotion of flowering by vernalization is that plants have evolved the ability to measure a complete winter season of cold and to 'remember' this prior cold exposure in the spring. Recent work in Arabidopsis demonstrates the molecular basis of this memory of winter: vernalization causes changes in the chromatin structure of a flowering repressor gene, FLOWERING LOCUS C (FLC), that switch this gene into a repressed state that is mitotically stable. A key component of the vernalization pathway, VERNALIZATION INSENSITIVE3 (VIN3), which is a PHD-domain-containing protein, is induced only after a prolonged period of cold. VIN3 is involved in initiating the modification of FLC chromatin structure. The stable silencing of FLC also requires the DNA-binding protein VERNALIZATION1 (VRN1) and the polycomb-group protein VRN2.

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AcclimatizationArabidopsisCold TemperatureFlowersGene Expression Regulation, PlantPlantsSeasonsJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, Non-P.H.S.Review

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Sibum Sung, Richard M Amasino. 2004. Vernalization and epigenetics: how plants remember winter.. https://doi.org/10.1016/j.pbi.2003.11.010

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