Absence of warmth permits epigenetic memory of winter in Arabidopsis

作者：Hepworth Jo; Antoniou Kourounioti Rea L; Bloomer Rebecca H; Selga Catja; Berggren Kristina; Cox Deborah; Harris Barley R Collier; Irwin Judith A; Holm Svante; Sall Torbjorn; Howard Martin; Dean Caroline

来源：Nature Communications, 2018, 9(1): 639.

DOI：10.1038/s41467-018-03065-7

Plants integrate widely fluctuating temperatures to monitor seasonal progression. Here, we investigate the temperature signals in field conditions that result in vernalisation, the mechanism by which flowering is aligned with spring. We find that multiple, distinct aspects of the temperature profile contribute to vernalisation. In autumn, transient cold temperatures promote transcriptional shutdown of Arabidopsis FLOWERING LOCUS C (FLC), independently of factors conferring epigenetic memory. As winter continues, expression of VERNALIZATION INSENSITIVE3 (VIN3), a factor needed for epigenetic silencing, is upregulated by at least two independent thermosensory processes. One integrates long-term cold temperatures, while the other requires the absence of daily temperatures above 15 degrees C. The lack of spikes of high temperature, not just prolonged cold, is thus the major driver for vernalisation. Monitoring of peak daily temperature is an effective mechanism to judge seasonal progression, but is likely to have deleterious consequences for vernalisation as the climate becomes more variable.

• 出版日期2018-2-12