Multiple loss-of-function of Arabidopsis gibberellin receptor AtGID1s completely shuts down a gibberellin signal
Multiple loss-of-function of Arabidopsis gibberellin receptor AtGID1s completely shuts down a gibberellin signal
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DOI：
10.1111/j.1365-313x.2007.03098.x
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发表时间：
2007-06-01
期刊：
影响因子：
7.2
通讯作者：
Nakajima, Masatoshi
中科院分区：
文献类型：
--
作者：
Iuchi, Satoshi;Suzuki, Hiroyuki;Nakajima, Masatoshi
拟南芥携带三种植物激素赤霉素（GA）的受体基因，AtGID 1a，AtGID 1b和AtGID 1c。在GA受体的水稻gid 1 -1突变体中每个基因的表达导致其严重矮化表型和GA不敏感性回复到正常水平，即使每个功能丧失突变体在拟南芥中没有显示出明确的表型（Nakajima等人，2006年）。在本文中，我们报告的功能冗余和特异性的每个AtGID 1通过分析多个突变体的功能丧失。双敲除突变体atgid 1a atgid 1b、atgid 1a atgid 1c和atgid 1b atgid 1c的种子萌发正常。双敲除突变体atgid 1a atgid 1c表现出矮小表型，而其他双突变体与野生型相比具有正常高度。双基因敲除突变体atgid 1a atgid 1b的雄蕊明显短于野生型，这导致了低生育力。还观察到其种子表面的图案严重紊乱。三重敲除突变体atgid 1a atgid 1b atgid 1c不会自动发芽，只有在浸泡后剥去种皮时才开始生长。三重基因敲除突变体的幼苗严重矮化，生长1个月后只有几毫米高。此外，三重基因敲除幼苗完全丧失了对外源GA的反应能力。这些结果表明，所有AtGID 1 s功能作为GA受体在拟南芥中，但有特定的作用（S）的生长和发育。
Arabidopsis carries three receptor genes for the phytohormone gibberellin (GA), AtGID1a, AtGID1b and AtGID1c. Expression of each gene in the rice gid1-1 mutant for GA receptors causes reversion of its severely dwarfed phenotype and GA insensitivity to a normal level, even though each loss-of-function mutant shows no clear phenotype in Arabidopsis (Nakajima et al., 2006). In this paper, we report the functional redundancy and specificity of each AtGID1 by analyzing the multiple mutants for loss of function. Seeds of the double knockout mutants atgid1a atgid1b, atgid1a atgid1c and atgid1b atgid1c germinated normally. The double knockout mutant atgid1a atgid1c showed a dwarf phenotype, while other double mutants were of normal height compared to the wild-type. The stamens of the double knockout mutant atgid1a atgid1b were significantly shorter than those of the wild-type, and this leads to low fertility. A severe disarrangement of the pattern on its seed surface was also observed. The triple knockout mutant atgid1a atgid1b atgid1c did not germinate voluntarily, and only started to grow when the seed coat was peeled off after soaking. Seedlings of the triple knockout mutants were severe dwarfs, only a few millimeters high after growing for 1 month. Moreover, the triple knockout seedlings completely lost their ability to respond to exogenously applied GA. These results show that all AtGID1s function as GA receptors in Arabidopsis, but have specific role(s) for growth and development.