Prof. Zeng Tao discovered the molecular pathway to reset ‘epigenetic memory of vernalization’ in plants

Recently research article “Embryonic resetting of the parental vernalized state by two B3 domain transcription factors in Arabidopsis”was published In Nature Plants, which discovered a molecular pathway to erase a parental environmental memory in early embryos in plants with plant-specific B3 transcriptional factors. Prof. Zeng Tao from biotechnology institute in our college contributed as first author.

After experiencing winter, over-wintering plants acquire competence to flower in the coming spring，which termed as vernalization. In Arabidopsis thaliana, the MADS-box transcription factor FLOWERING LOCUS C (FLC) acts to inhibit flowering prior to cold, and prolonged cold induces FLC epigenetic silencing. When the temperature rises, the silenced state is epigenetically maintained or ‘memorized’ in subsequent growth and development, rendering plants competent to flower. But this ‘epigenetic memory of winter cold’ must be erased or reset in next generation to ensure each generation needs to be exposed to winter cold prior to flowering.

These findings, presented recently in Nature Plants, show that in early embryos two embryonic B3-domain transcription factors known as LEC2 and FUS3 compete against VAL1 and VAL2 for the cis-regulatory CME at the FLC locus to disrupt the PcG-mediated chromatin silencing. This study illustrates an elegant and sophisticated mechanism for the overwintering crucifer plants to synchronize their growth and development with cyclic seasonal temperature changes: engaging four plant-specific B3 transcriptional factors to switch on, off and on again to regulate the expression of a potent flowering inhibitor in the embryo-to-plant-to-embryo life cycle.

This study led by Dr. Yuehui He and Dr. Jiamu Du from Shanghai Center for Plant Stress biology CAS and support by the funds from the National Natural Science Fund and the National Key Research Development Program.