National Key Laboratory of Plant Molecular Genetics (NKLPMG), Institute of Plant Physiology and Ecology (SIPPE), Shanghai Institutes for Biological Sciences (SIBS), Shanghai, P R China.
Science. 2013 May 31;340(6136):1097-100. doi: 10.1126/science.1234340.
Plants flower in response to many varied cues, such as temperature, photoperiod, and age. The floral transition of Cardamine flexuosa, a herbaceous biennial-to-perennial plant, requires exposure to cold temperature, a treatment known as vernalization. C. flexuosa younger than 5 weeks old are not fully responsive to cold treatment. We demonstrate that the levels of two age-regulated microRNAs, miR156 and miR172, regulate the timing of sensitivity in response to vernalization. Age and vernalization pathways coordinately regulate flowering through modulating the expression of CfSOC1, a flower-promoting MADS-box gene. The related annual Arabidopsis thaliana, which has both vernalization and age pathways, does not possess an age-dependent vernalization response. Thus, the recruitment of age cue in response to environmental signals contributes to the evolution of life cycle in plants.
植物会根据多种不同的线索开花，如温度、光周期和年龄。作为一种二年生到多年生的草本植物，屈曲碎米荠的花期转变需要经历低温诱导，这个过程被称为春化作用。年龄小于 5 周的屈曲碎米荠幼苗对低温处理不完全响应。我们证明，两个与年龄相关的 microRNA（miR156 和 miR172）的水平调节了对春化作用的敏感性的时间。年龄和春化途径通过调节 CfSOC1 的表达来协调调控开花，CfSOC1 是一个促进花发育的 MADS-box 基因。相关的一年生拟南芥既有春化途径又有年龄途径，但它没有年龄依赖性的春化响应。因此，植物对环境信号的年龄线索的响应有助于其生命周期的进化。
