Asymmetric Auxin Response Precedes Asymmetric Growth and Differentiation of asymmetric leaf1 and asymmetric leaf2 Arabidopsis Leaves
Asymmetric Auxin Response Precedes Asymmetric Growth and Differentiation of asymmetric leaf1 and asymmetric leaf2 Arabidopsis Leaves
复制标题
DOI：
10.1105/tpc.104.026898
复制
发表时间：
2005-01
期刊：
影响因子：
--
通讯作者：
J. Zgurski;Rita Sharma;Dee A. Bolokoski;E. Schultz
中科院分区：
文献类型：
--
作者：
J. Zgurski;Rita Sharma;Dee A. Bolokoski;E. Schultz
我们分析了不对称叶1（AS 1）或AS 2的叶突变体的叶形状和维管模式的发育，并比较了发育标志与细胞对生长素的反应的时间，如通过表达DR 5：β-葡萄糖醛酸酶（GUS）转基因和细胞分裂的时间，如通过表达cycB 1：GUS转基因。我们发现as 1和as 2第一片叶中最早可见的缺陷是生长素反应在远端叶尖的不对称位置。这先于可见的变化，叶形态，远端边缘间隙的不对称放置，边缘间隙沿着叶缘形成，边缘生长素的不对称分布，和细胞分裂模式的不对称。此外，用外源生长素或生长素运输抑制剂处理发育中的叶片消除了不对称生长素反应和随后的不对称叶片发育。我们认为，叶尖生长素最初的不对称放置会导致内部生长素来源的不对称，从而导致细胞分化和分裂模式的不对称。
We have analyzed the development of leaf shape and vascular pattern in leaves mutant for ASYMMETRIC LEAVES1 (AS1) or AS2 and compared the timing of developmental landmarks to cellular response to auxin, as measured by expression of the DR5:β-glucuronidase (GUS) transgene and to cell division, as measured by expression of the cycB1:GUS transgene. We found that the earliest visible defect in both as1 and as2 first leaves is the asymmetric placement of auxin response at the distal leaf tip. This precedes visible changes in leaf morphology, asymmetric placement of the distal margin gap, formation of margin gaps along the leaf border, asymmetric distribution of marginal auxin, and asymmetry in cell division patterns. Moreover, treatment of developing leaves with either exogenous auxin or an auxin transport inhibitor eliminates asymmetric auxin response and subsequent asymmetric leaf development. We propose that the initial asymmetric placement of auxin at the leaf tip gives rise to later asymmetries in the internal auxin sources, which subsequently result in asymmetrical cell differentiation and division patterns.