Molecular Ecology of Flowering Regulation Pathways: Flowering Regulation in the Natural Conditions

环境温度和光周期是植物感知季节变化的主要线索。与光周期沿着日历的可预测性质相反，温度的季节性模式仅表现为长期趋势。因此，植物需要一个对温度变化的长期趋势敏感但对短期波动敏感的分子系统。在这里，我们表明，Polycomb组（PcG）蛋白质介导的转录因子，FLOWCOMB LOCUS C（FLC），作为一个关键的机制，长期整合的环境温度波动在常年的生命周期。我们在自然生长的植物叶片中定量FLC表达一年，在约100 ℃。一周的时间间隔在一个自然群体的多年生拟南芥halleri ssp.芽层与年度A.在拟南芥中，FLC阻遏的重置在多年生生活史中不通过世代发生。FLC水平与过去的温度制度高度相关。FLC的抑制和增加均具有温度依赖性。FLC表达的季节性模式不仅与植物-生殖转换的时间相对应，而且与反向转换的时间相对应。我们的结论是，FLC是不是mealy的冬季记忆，但更具有包容性的作用，作为一个长期的温度波动的定量示踪剂的季节性阶段控制在常年的生活史。

Ambient temperature and photoperiod are known to be the major cues for plants to sense seasons. Contrary to the predictable nature of photoperiod along the calendar, the seasonal pattern of temperature only appears as a long-term trend. Therefore, plants require a molecular system that is sensitive to the long-term trend of temperature change but to the short-term fluctuations. Here we show that the Polycomb group (PcG) protein mediated transcription factor, FLOWERING LOCUS C (FLC), serves as a key mechanism for long-term integration of fluctuating ambient temperature in the perennial life cycle. We quantified FLC expression in leaves of naturally growing plants for a year at ca. one week intervals in a natural population of the perennial Arabidopsis halleri ssp. gemmifera. Contrary to what is known in the annual A. thaliana, reset of FLC repression occurs without passing generation in the perennial life cycle. FLC levels were highly associated with temperature regimes for past ca. 5 weeks throughout the year, and both suppression and increment of FLC were temperature-dependent. The seasonal pattern in FLC expression corresponded not only to the timing of vegetative-reproductive transition but also to the timing of the reverse transition. We concluded that FLC is not mealy a memory of winter but have more inclusive role as a quantitative tracer of long-term temperature fluctuation for seasonal phase control in the perennial life-cycle.