Cytokinin overproduction-caused alteration of flower development is partially mediated by CUC2 and CUC3 in Arabidopsis
Cytokinin overproduction-caused alteration of flower development is partially mediated by CUC2 and CUC3 in Arabidopsis
复制标题
拟南芥中细胞分裂素过量产生导致的花发育改变部分由 CUC2 和 CUC3 介导
DOI：
10.1016/j.gene.2009.11.003
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发表时间：
2010-01-15
期刊：
影响因子：
3.5
通讯作者：
Zhang, Xian Sheng
中科院分区：
文献类型：
--
作者：
Li, Xing Guo;Su, Ying Hua;Zhang, Xian Sheng
细胞分裂素是许多植物生长和发育过程中必不可少的调节剂。然而，对细胞分裂素调控花发育的机制知之甚少。在本研究中，我们发现，花特异性海拔的细胞分裂素通过转基因表达的拟南芥ATP/ADP异戊烯基转移酶4（AtIPT 4）基因的APETALA 1（AP 1）启动子的控制下，导致花发育的改变。这些变化包括花数增加和花发育异常，与花序和花分生组织增大有关。全基因组表达谱分析显示，大量的基因对细胞分裂素水平的增加有反应，包括首次报道的杯形子叶2（CUC 2）和CUC 3的表达被细胞分裂素升高。进一步分析表明，cuc 2或cuc 3的突变减弱了由AP 1：：AtIPT 4转基因引起的表型。细胞分裂素受体拟南芥组氨酸激酶2（AHK 2）和AHK 3的突变几乎取消了转基因表型和细胞分裂素诱导的CUC 2和CUC 3转录增强。我们的研究结果表明，花原基中过量产生的细胞分裂素主要通过AHK 2和AHK 3信号传导导致效应基因CUC 2和CUC 3的表达增加而导致花发育的改变。因此，由AHK 2和AHK 3信号传导介导的CUC 2和CUC 3的表达可能在花发育的调控中起作用。(C)2009 Elsevier B. V.保留所有权利。
Cytokinin is an essential regulator of numerous plant growth and developmental processes. However, less is known about the mechanisms of cytokinin-regulated floral development. In the present study, we found that flower-specific elevation of cytokinin through transgenic expression of an Arabidopsis ATP/ADP isopentenyltransferase 4 (AtIPT4) gene under the control of the APETALA1 (AP1) promoter lead to floral developmental alterations. These changes included promotion of the number of flowers and abnormal development of flowers, which were correlated with enlarged inflorescence and flower meristems. Genome-wide expression profiling revealed that a large number of genes were responsive to increased cytokinin levels, including this first report that the expression of CUP-SHAPED COTYLEDON2 (CUC2) and CUC3 is elevated by cytokinin. Further analysis showed that mutation of cuc2 or cuc3 attenuates the phenotypes ;caused by the AP1: :AtIPT4 transgene. Mutation of the cytokinin receptors Arabidopsis histidine kinase 2 (AHK2) and AHK3 nearly abolished the transgene phenotypes and the enhanced CUC2 and CUC3 transcription induced by cytokinin. Our results indicate that the overproduced cytokinin in flower primordia results in alteration of floral development mainly through AHK2 and AHK3 signaling leading to increased expression of the effector genes CUC2 and CUC3. Thus, it is likely that the CUC2 and CUC3 expression mediated by AHK2 and AHK3 signaling may play roles in regulation of flower development. (C) 2009 Elsevier B.V. All rights reserved.