Cotyledon Vascular Pattern2-mediated inositol (1,4,5) triphosphate signal transduotion is essential for closed venation patterns of Arabidolpsis foliar organs
Cotyledon Vascular Pattern2-mediated inositol (1,4,5) triphosphate signal transduotion is essential for closed venation patterns of Arabidolpsis foliar organs
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DOI：
10.1105/tpc.021030
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发表时间：
2004-05-01
期刊：
影响因子：
11.6
通讯作者：
Nelson, T
中科院分区：
文献类型：
--
作者：
Carland, FM;Nelson, T
叶子和子叶中的静脉图案通过基本细胞逐渐招募进入维管细胞命运而以空间调节的方式形成。为了深入了解脉序模式的机制，我们已经表征了子叶血管模式2（cvp2）突变体，其表现出增加自由静脉末梢和由此产生的开放静脉网络。我们通过图位克隆策略克隆了CVP2，发现它编码肌醇多磷酸5'磷酸酶（5PTase）。5PTases通过水解IP3来调节IP3信号转导，从而终止IP3信号转导。CVP2基因的表达最初是广泛的，然后逐渐限制在几个发育器官的初期血管细胞。与推断的CVP 2的酶活性一致，IP3水平在cvp2突变体中升高。此外，cvp2突变体表现出对植物激素脱落酸的超敏反应。我们建议，IP3水平升高cvp2突变体减少地面细胞招募到血管细胞的命运，导致过早静脉终止，因此，在一个开放的网状。
Vein patterns in leaves and cotyledons form in a spatially regulated manner through the progressive recruitment of ground cells into vascular cell fate. To gain insight into venation patterning mechanisms, we have characterized the cotyledon vascular pattern2 (cvp2) mutants, which exhibit an increase in free vein endings and a resulting open vein network. We cloned CVP2 by a map-based cloning strategy and found that it encodes an inositol polyphosphate 5' phosphatase (5PTase). 5PTases regulate inositol (1,4,5) triphosphate (IP3) signal transduction by hydrolyzing IP3 and thus terminate IP3 signaling. CVP2 gene expression is initially broad and then gradually restricted to incipient vascular cells in several developing organs. Consistent with the inferred enzymatic activity of CVP2, IP3 levels are elevated in cvp2 mutants. In addition, cvp2 mutants exhibit hypersensitivity to the plant hormone abscisic acid. We propose that elevated IP3 levels in cvp2 mutants reduce ground cell recruitment into vascular cell fate, resulting in premature vein termination and, thus, in an open reticulum.