ASYMMETRIC LEAVES1 and auxin activities converge to repress BREVIPEDICELLUS expression and promote leaf development in Arabidopsis
ASYMMETRIC LEAVES1 and auxin activities converge to repress BREVIPEDICELLUS expression and promote leaf development in Arabidopsis
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DOI：
10.1242/dev.02545
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发表时间：
2006-10-15
期刊：
影响因子：
4.6
通讯作者：
Tsiantis, Miltos
中科院分区：
文献类型：
--
作者：
Hay, Angela;Barkoulas, Michalis;Tsiantis, Miltos
在高等植物中，叶的发育需要在一个多能性结构（称为茎尖分生组织）的两侧特异化叶的原始细胞。在拟南芥中，这一过程是由I类KNOTTED1样同源框（KNOX）和不对称叶1（AS1）转录因子之间的负相互作用促进的，这样KNOX蛋白被限制在分生组织中，而AS1被限制在叶的起始处。叶开始的网站也定义了当地积累的激素生长素，但是，它是未知的生长素和AS1活动是如何整合到控制叶的发展。在这里，我们表明，生长素和AS1途径收敛到抑制表达的KNOX基因短杆菌（BP），从而促进叶的命运。我们还表明，调节生长素梯度控制叶片形状在一个KNOX独立的方式和不适当的KNOX活性叶片扰动这些梯度，从而改变叶片形状。我们建议，生长素，AS1和KNOX活动之间的相互作用，可以直接叶片启动和造型叶片的形式。
Leaf development in higher plants requires the specification of leaf initials at the flanks of a pluripotent structure termed the shoot apical meristem. In Arabidopsis, this process is facilitated by negative interactions between class I KNOTTED1-like homeobox (KNOX) and ASYMMETRIC LEAVES1 (AS1) transcription factors, such that KNOX proteins are confined to the meristem and AS1 to leaf initials. Sites of leaf inception are also defined by local accumulation of the hormone auxin; however, it is unknown how auxin and AS1 activities are integrated to control leaf development. Here, we show that auxin and AS1 pathways converge to repress expression of the KNOX gene BREVIPEDICELLUS (BP) and thus promote leaf fate. We also demonstrate that regulated auxin gradients control leaf shape in a KNOX-independent fashion and that inappropriate KNOX activity in leaves perturbs these gradients, hence altering leaf shape. We propose that regulatory interactions between auxin, AS1 and KNOX activities may both direct leaf initiation and sculpt leaf form.