Aberrant Stamen Development is Associated with Parthenocarpic Fruit Set Through Up-Regulation of Gibberellin Biosynthesis in Tomato
Aberrant Stamen Development is Associated with Parthenocarpic Fruit Set Through Up-Regulation of Gibberellin Biosynthesis in Tomato
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DOI：
10.1093/pcp/pcy184
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发表时间：
2018-09
影响因子：
4.9
通讯作者：
Yoshihiro Okabe;Tatsuya Yamaoka;T. Ariizumi;K. Ushijima;M. Kojima;Yumiko Takebayashi;H. Sakakibara;M. Kusano;Yoshihito Shinozaki;Sri Imriani Pulungan;Y. Kubo;R. Nakano;H. Ezura
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文献类型：
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作者：
Yoshihiro Okabe;Tatsuya Yamaoka;T. Ariizumi;K. Ushijima;M. Kojima;Yumiko Takebayashi;H. Sakakibara;M. Kusano;Yoshihito Shinozaki;Sri Imriani Pulungan;Y. Kubo;R. Nakano;H. Ezura
单性生殖是一种在没有受精的情况下坐果的过程，导致无籽果实的产生。一些雄蕊发育异常的花同源突变体表现为单性果核。花的发育被认为在花期前抑制子房的生长。然而，由于花的异常形成导致孤雌果实发育的机制尚不清楚。为了研究花同源突变体单性果实发育的分子机制，我们采用功能缺失法对番茄APETALA3 （TAP3）进行了功能分析。利用器官特异性启动子诱导雄蕊和子房/果实器官特异性功能丧失。我们观察到在孤雌果实生长过程中，tap3突变体和tap3 - rnai系的细胞扩增增加。这些主要伴随着GA生物合成基因SlGA20ox1、SlGA20ox2和SlGA20ox3的上调，GA失活基因SlGA2ox1和参与GA与生长素串扰的生长素信号传导基因SlARF7的表达降低。这些转录谱与这些细胞系中的GA水平一致。这些结果表明，雄蕊发育通过抑制GA生物合成负向调控坐果。
Parthenocarpy, a process in which fruit set occurs without fertilization, leads to the production of seedless fruit. A number of floral homeotic mutants with abnormal stamen development exhibit parthenocarpic fruit set. Flower development is thought to repress ovary growth before anthesis. However, the mechanism of parthenocarpic fruit development caused by aberrant flower formation is poorly understood. To investigate the molecular mechanism of parthenocarpic fruit development in floral homeotic mutants, we performed functional analysis of Tomato APETALA3 (TAP3) by loss-of-function approaches. Organ-specific promoter was used to induce organ-specific loss of function in stamen and ovary/fruit. We observed increased cell expansion in tap3 mutants and TAP3-RNAi lines during parthenocarpic fruit growth. These were predominantly accompanied by the up-regulation of GA biosynthesis genes, including SlGA20ox1, SlGA20ox2, and SlGA20ox3, as well as reduced expression of the GA-inactivating gene SlGA2ox1 and the auxin signaling gene SlARF7 involved in a crosstalk between GA and auxin. These transcriptional profiles are in agreement with the GA levels in these lines. These results suggest that stamen development negatively regulates fruit set by repressing the GA biosynthesis.