Institute of Plant Sciences, Agricultural Research Organization, The Volcani Center, Rishon LeZion, Israel.
Institute of Plant Sciences, Agricultural Research Organization, The Volcani Center, Rishon LeZion, Israel.
Plant Sci. 2020 Dec;301:110678. doi: 10.1016/j.plantsci.2020.110678. Epub 2020 Sep 18.
We identified a pepper late-flowering mutant that is disrupted in the sequence of CaFT-LIKE, the ortholog of tomato SINGLE FLOWER TRUSS (SFT). Heterologous expression in tomato indicated that CaFT-LIKE has a conserved function as a flowering promoter and can rescue the wild-type phenotype of the tomato sft mutant. CaFT-LIKE confers a graft-transmissible signal for flowering initiation in tomato, implicating its function as a florigen. To test the relationship between CaFT-LIKE and FASCICULATE (FA), the ortholog of tomato SELF PRUNING (SP), we constructed the double mutant Caft-like fa. The phenotype of Caft-like fa resembled that of Caft-like, indicating epistasis of Caft-like over fa in controlling flowering time and sympodial shoot structure. To examine the association between the expression pattern of flowering genes and natural variation in flowering time, the expression levels of CaFT-LIKE and the flowering repressor CaAP2 were determined in a panel of early-flowering cultivars and late-flowering landraces and wild accessions. Strong positive and negative correlations between flowering time and expression levels of CaAP2 and CaFT-LIKE, respectively, were observed, indicating that high-expression alleles of CaFT-LIKE and low-expression alleles of CaAP2 were selected for early flowering during pepper domestication and breeding.
我们鉴定了一个辣椒晚花突变体,该突变体在 CaFT-LIKE 的序列中发生了突变,CaFT-LIKE 是番茄 SINGLE FLOWER TRUSS (SFT) 的同源物。在番茄中的异源表达表明,CaFT-LIKE 具有作为开花促进剂的保守功能,并能挽救番茄 sft 突变体的野生型表型。CaFT-LIKE 赋予了番茄开花起始的可嫁接信号,暗示其作为成花素的功能。为了测试 CaFT-LIKE 与番茄 SELF PRUNING (SP) 的同源物 FASCICULATE (FA) 之间的关系,我们构建了双突变体 Caft-like fa。Caft-like fa 的表型与 Caft-like 相似,表明 Caft-like 在控制开花时间和合轴状分枝结构方面对 fa 具有上位性。为了检验开花基因表达模式与开花时间自然变异之间的关系,我们在一组早花品种和晚花地方品种和野生材料中测定了 CaFT-LIKE 和开花抑制子 CaAP2 的表达水平。开花时间与 CaAP2 和 CaFT-LIKE 的表达水平之间存在强烈的正相关和负相关,表明在辣椒驯化和选育过程中,高表达的 CaFT-LIKE 等位基因和低表达的 CaAP2 等位基因被选择用于早期开花。