A Role for GIBBERELLIN 2-OXIDASE6 and Gibberellins in Regulating Nectar Production
A Role for GIBBERELLIN 2-OXIDASE6 and Gibberellins in Regulating Nectar Production
复制标题
赤霉素 2-氧化酶 6 和赤霉素在调节花蜜生产中的作用
DOI：
10.1016/j.molp.2015.12.019
复制
发表时间：
2016
期刊：
影响因子：
27.5
通讯作者：
Carter, Clay J.
中科院分区：
文献类型：
--
作者：
Wiesen, Lisa B.;Bender, Ricci L.;Paradis, Travis;Larson, Alexie;Perera, M. Ann D.N.;Nikolau, Basil J.;Olszewski, Neil E.;Carter, Clay J.
花蜜产生的调节依赖于激素信号传导。例如，编码生长素外排转运蛋白家族蛋白的拟南芥PIN6被鉴定为蜜腺富集基因，其表达水平与总花蜜产量呈正相关（Bender等人，2013）。此外，茉莉酸 (JA) 水平在开花前在芸苔属花中达到峰值，并促进花蜜分泌（Radhika 等人，2010）。虽然生长素和 JA 已被证明在花蜜生产的调节中发挥作用，但尚不清楚其他植物激素对此过程的影响。在这里，我们报告赤霉素（GA）也影响拟南芥的蜜腺功能。微阵列数据分析（参见补充信息和补充图1）表明GA 2-OXIDASE6（GA2ox6，At1g02400）在成熟的分泌性蜜腺中表达丰富（图1A-1）。这种表达模式通过在 3 kb GA2ox6 启动子（GA2ox6pro：GUS；图 1 A-2 和 1A-3）控制下表达 GUS 报告基因的转基因植物以及花前和花后花转录物的终点 RT-PCR 分析（图 1 A-1D）得到证实。在蜜腺中显示可测量转录本的唯一其他 GA 2-氧化酶是 GA2ox2 和 GA2ox8，尽管它们在成熟的侧蜜腺中的表达水平远低于 GA2ox6（参见补充图 1）。
The regulation of nectar production is dependent on hormonal signaling. For example, Arabidopsis PIN6, which encodes an auxin efflux transporter family protein, was identified as a nectary-enriched gene whose expression level was positively correlated to total nectar production (Bender et al., 2013). Furthermore, jasmonic acid (JA) levels peak in Brassica flowers just prior to anthesis and promote nectar secretion (Radhika et al., 2010). While auxin and JA have been demonstrated to play roles in the regulation of nectar production, it is unclear about the impacts other phytohormones have on this process. Here we report that gibberellins (GAs) also affect nectary function in Arabidopsis thaliana.Analysis of microarray data (see Supplemental Information and Supplemental Figure 1) suggested that GA 2-OXIDASE6 (GA2ox6, At1g02400) had enriched expression in mature, secretory nectaries (Figure 1 A-1). This expression pattern was confirmed through transgenic plants expressing the GUS reporter gene under the control of 3 kb of the GA2ox6 promoter (GA2ox6pro: GUS; Figure 1 A-2 and 1A-3) and endpoint RT–PCR analyses of transcripts in pre-and postanthesis flowers (Figure 1 A–1D). The only other GA 2-oxidases displaying measurable transcript in nectaries were GA2ox2 and GA2ox8, although both were expressed at much lower levels than GA2ox6 in mature, lateral nectaries (see Supplemental Figure 1).