A role of brassinosteroids in early fruit development in cucumber
A role of brassinosteroids in early fruit development in cucumber
复制标题
油菜素类固醇在黄瓜早期果实发育中的作用
DOI：
10.1093/jxb/ern093
复制
发表时间：
2008-06-01
影响因子：
6.9
通讯作者：
Yu, Jing Quan
中科院分区：
文献类型：
--
作者：
Fu, Feng Qing;Mao, Wei Hua;Yu, Jing Quan
油菜素内酯（BRs）对植物的许多生物过程至关重要，但对其在果实早期发育中的作用知之甚少。为了解决这一问题，研究人员通过外源BRs（24-表油菜素内酯，EBR）或BR生物合成抑制剂（油菜素唑，Brz）控制BR水平，并在两种不同单性繁殖能力的黄瓜品种中检测了它们对早期果实发育、细胞分裂以及细胞周期蛋白和细胞周期蛋白依赖性激酶（CDKs）基因表达的影响。EBR处理对无单性生殖能力的金春4号植株产生了单性生殖生长和活跃的细胞分裂，而Brz处理对具有天然单性生殖能力的金春2号植株坐果产生抑制作用，进而抑制了果实的生长，EBR处理可以恢复这种抑制作用。RT-PCR分析显示，授粉和EBR均诱导开花后细胞周期相关基因（CycA、CycB、CycD3;1、CycD3；2和CDKB）的表达。CsCycD3 cDNA序列；1和CsCycD3；经PCR扩增分离得到2株。CsCycD3;1和CsCycD3；2个转录本在EBR处理和授粉中表达上调，而在Brz处理中表达强烈抑制。同时，BR6ox1和SMT转录本这两个参与BR合成的基因表现出反馈调控。这些结果表明，BRs在黄瓜果实早期发育过程中起着重要作用。
Brassinosteroids (BRs) are essential for many biological processes in plants, however, little is known about their roles in early fruit development. To address this, BR levels were manipulated through the application of exogenous BRs (24-epibrassinolide, EBR) or a BR biosynthesis inhibitor (brassinazole, Brz) and their effects on early fruit development, cell division, and expression of cyclin and cyclin-dependent kinases (CDKs) genes were examined in two cucumber cultivars that differ in parthenocarpic capacity. The application of EBR induced parthenocarpic growth accompanied by active cell division in Jinchun No. 4, a cultivar without parthenocarpic capacity, whereas Brz treatment inhibited fruit set and, subsequently, fruit growth in Jinchun No. 2, a cultivar with natural parthenocarpic capacity, and this inhibitory effect could be rescued by the application of EBR. RT-PCR analysis showed both pollination and EBR induced expression of cell cycle-related genes (CycA, CycB, CycD3;1, CycD3;2, and CDKB) after anthesis. cDNA sequences for CsCycD3;1 and CsCycD3;2 were isolated through PCR amplification. Both CsCycD3;1 and CsCycD3;2 transcripts were up-regulated by EBR treatment and pollination but strongly repressed by Brz treatment. Meanwhile, BR6ox1 and SMT transcripts, two genes involved in BR synthesis, exhibited feedback regulation. These results strongly suggest that BRs play an important role during early fruit development in cucumber.