Auxin-mediated lamina growth in tomato leaves is restricted by two parallel mechanisms
Auxin-mediated lamina growth in tomato leaves is restricted by two parallel mechanisms
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DOI：
10.1111/tpj.13188
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发表时间：
2016-06-01
期刊：
影响因子：
7.2
通讯作者：
Ori, Naomi
中科院分区：
文献类型：
--
作者：
Ben-Gera, Hadas;Dafna, Asaf;Ori, Naomi
在番茄复叶的发育中，由Aux/IAA蛋白SlIAA 9/ENTIRE（E）的表达分隔的局部生长素最大点指导沿着叶缘沿着形成离散小叶。局部生长素极大促进小叶起始，而E在小叶之间起作用以抑制生长素反应和叶片生长，使小叶分离。在这里，我们表明，一组生长素反应因子（ARF），这是由miR 160的目标，拮抗生长素反应和叶片生长与E。在野生型叶原基中，靶向miR 160的ARF SlARF 10A和SlARF 17在小叶中表达，而SlmiR 160在原血管组织中表达。miR 160靶向的ARF SlARF 10A、SlARF 10 B或SlARF 17的叶过表达导致叶片减少和叶复杂性增加，并抑制幼叶中的生长素反应。一致的是，miR 160的叶过表达导致简化的叶，这是由于小叶之间的异位叶片生长，使人联想到e叶。遗传相互作用表明，E和miR 160靶向的ARF部分冗余地起作用，但都是局部抑制起始小叶之间的叶片生长所必需的。这些结果表明，不同类型的生长素信号拮抗剂协同作用，以确保在番茄叶缘小叶分离。
In the development of tomato compound leaves, local auxin maxima points, separated by the expression of the Aux/IAA protein SlIAA9/ENTIRE (E), direct the formation of discrete leaflets along the leaf margin. The local auxin maxima promote leaflet initiation, while E acts between leaflets to inhibit auxin response and lamina growth, enabling leaflet separation. Here, we show that a group of auxin response factors (ARFs), which are targeted by miR160, antagonizes auxin response and lamina growth in conjunction with E. In wild-type leaf primordia, the miR160-targeted ARFs SlARF10A and SlARF17 are expressed in leaflets, and SlmiR160 is expressed in provascular tissues. Leaf overexpression of the miR160-targeted ARFs SlARF10A, SlARF10B or SlARF17, led to reduced lamina and increased leaf complexity, and suppressed auxin response in young leaves. In agreement, leaf overexpression of miR160 resulted in simplified leaves due to ectopic lamina growth between leaflets, reminiscent of e leaves. Genetic interactions suggest that E and miR160-targeted ARFs act partially redundantly but are both required for local inhibition of lamina growth between initiating leaflets. These results show that different types of auxin signal antagonists act cooperatively to ensure leaflet separation in tomato leaf margins.