BcMAF2 activates BcTEM1 and represses flowering in Pak-choi (Brassica rapa ssp. chinensis)
BcMAF2 activates BcTEM1 and represses flowering in Pak-choi (Brassica rapa ssp. chinensis)
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DOI：
10.1007/s11103-019-00867-1
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发表时间：
2019-05-01
影响因子：
5.1
通讯作者：
Hou, Xilin
中科院分区：
文献类型：
--
作者：
Huang, Feiyi;Liu, Tongkun;Hou, Xilin
关键信息BcMAF 2通过转录BcTEM 1、BcSOC 1和BCSPL 15在小白菜的开花调控中发挥关键作用。不同品种小白菜的开花时间差异较大。chinensis）栽培品种。然而，小白菜开花的调控机制仍然知之甚少。本研究对小白菜MADS基因BcMAF 2进行了系统的鉴定和功能分析。BcMAF 2编码一个保守的MADS-box结构域，定位于细胞核内。QPCR分析表明，BcMAF 2在叶片和花中的表达量较高。BcMAF 2在拟南芥中的过表达表明，BcMAF 2抑制开花，这进一步证实了沉默内源BcMAF 2在小白菜。此外，在BcMAF 2过表达的拟南芥中，Tempranillo 1（TEM 1）表达上调，MAF 2表达下调。BcMAF 2基因沉默的小白菜中BcMAF 2和BcTEM 1基因的表达下调。酵母单杂交、双荧光素酶和qPCR结果表明，BcMAF 2蛋白能直接与BcTEM 1启动子结合并激活其表达，这在拟南芥中未见报道。同时，BcMAF 2具有自抑制作用。综上所述，这项工作表明BcMAF 2可以通过直接激活BcTEM 1来抑制开花。
Key messageBcMAF2plays a key role in flowering regulation by controllingBcTEM1, BcSOC1andBCSPL15in Pak-choi.AbstractFlowering is a key event in the life cycle of plants. Flowering time shows an extensive variation from different Pak-choi (Brassica rapa ssp. chinensis) cultivars. However, the regulation mechanism of flowering in Pak-choi remains rarely known. In this study, a systematic identification and functional analysis of a Pak-choi MADS Affecting Flowering (MAF) gene, BcMAF2, was carried out. BcMAF2 encoded a protein containing a conserved MADS-box domain, which was localized in the nucleus. QPCR analysis indicated that the expression of BcMAF2 was higher in the leaves and flowers. Overexpression of BcMAF2 in Arabidopsis showed that BcMAF2 repressed flowering, which was further confirmed by silencing endogenous BcMAF2 in Pak-choi. In addition, Tempranillo 1 (TEM1) expression was up-regulated and MAF2 expression was down-regulated in the BcMAF2-overexpressing Arabidopsis. The expression of BcMAF2 and BcTEM1 was down-regulated in BcMAF2-silencing Pak-choi plants. The yeast one-hybrid, dual luciferase and qPCR results revealed that BcMAF2 protein could directly bind to BcTEM1 promoter and activate its expression, which was not reported in Arabidopsis. Meanwhile, a self-inhibition was found in BcMAF2. Taken together, this work suggested that BcMAF2 could repress flowering by directly activating BcTEM1.