Discrete developmental roles for temperate cereal grass VERNALIZATION1/FRUITFULL-like genes in flowering competency and the transition to flowering
Discrete developmental roles for temperate cereal grass VERNALIZATION1/FRUITFULL-like genes in flowering competency and the transition to flowering
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DOI：
10.1104/pp.107.109561
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发表时间：
2008-01-01
期刊：
影响因子：
7.4
通讯作者：
Kellogg, Elizabeth A.
中科院分区：
文献类型：
--
作者：
Preston, Jill C.;Kellogg, Elizabeth A.
草亚科的成员以适应寒冷的温带气候为特征。春化是指在长时间的寒冷中加速开花的过程。冬粮耐低温，春化开花早，春化不耐低温，开花晚。在杂草小麦和大麦中，春化反应是由VRN1和/或VRN2基因座上的等位基因变异决定的。为了确定VRN1及其同源基因FRUITFULL2(FUL2)是否参与了燕麦亚科植物的春化需求，我们测定了多个燕麦品种和小麦在冷处理前后的表达谱。我们的结果表明，春化显著上调了冬季燕麦和小麦叶片中VRN1的表达；对春季或兼性生长习性燕麦和小麦没有发现处理效果。在冬小麦中，FUL2的叶片表达与冷相关的模式相似，但不是冬小麦，这表明这些基因在燕麦开花能力的数量诱导中具有多余的质量作用。这些数据和其他数据支持这样的假设，即VRN1是冠突体内春化反应的共同调节因子。最后，我们发现VRN1在燕麦营养分生组织中的上调明显晚于叶片。这表明温带谷类植物VRN1/FUL类基因具有独特而保守的功能，第一，在诱导开花能力的系统信号中，第二，在分生组织中，激活与花转换相关的基因。
Members of the grass subfamily Pooideae are characterized by their adaptation to cool temperate climates. Vernalization is the process whereby flowering is accelerated in response to a prolonged period of cold. Winter cereals are tolerant of low temperatures and flower earlier with vernalization, whereas spring cultivars are intolerant of low temperatures and flower later with vernalization. In the pooid grasses wheat (Triticum monococcum, Triticum aestivum) and barley (Hordeum vulgare), vernalization responsiveness is determined by allelic variation at the VERNALIZATION1 (VRN1) and/or VRN2 loci. To determine whether VRN1, and its paralog FRUITFULL2 (FUL2), are involved in vernalization requirement across Pooideae, we determined expression profiles for multiple cultivars of oat (Avena sativa) and wheat with and without cold treatment. Our results demonstrate significant up-regulation of VRN1 expression in leaves of winter oat and wheat in response to vernalization; no treatment effect was found for spring or facultative growth habit oat and wheat. Similar cold-dependent patterns of leaf expression were found for FUL2 in winter oat, but not winter wheat, suggesting a redundant qualitative role for these genes in the quantitative induction of flowering competency of oat. These and other data support the hypothesis that VRN1 is a common regulator of vernalization responsiveness within the crown pooids. Finally, we found that up- regulation of VRN1 in vegetative meristems of oat was significantly later than in leaves. This suggests distinct and conserved roles for temperate cereal grass VRN1/FUL-like genes, first, in systemic signaling to induce flowering competency, and second, in meristems to activate genes involved in the floral transition.