SEUSS and SEUSS-LIKE Transcriptional Adaptors Regulate Floral and Embryonic Development in Arabidopsis
SEUSS and SEUSS-LIKE Transcriptional Adaptors Regulate Floral and Embryonic Development in Arabidopsis
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DOI：
10.1104/pp.109.146183
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发表时间：
2010-02-01
期刊：
影响因子：
7.4
通讯作者：
Franks, Robert G.
中科院分区：
文献类型：
--
作者：
Bao, Fang;Azhakanandam, Sridevi;Franks, Robert G.
在发育过程中需要多聚体蛋白复合物来调节转录和协调细胞增殖和分化。拟南芥（Arabidopsis thaliana） SEUSS （SEU）基因编码一个转录适配器，该转录适配器与后生动物Lim结构域结合转录适配器序列相似。在拟南芥中，SEU与LEUNIG转录共调节因子形成物理复合物。该复合体调节着许多不同的发育事件，包括花器官身份和数量的适当规范以及来自心皮边缘分生组织的雌性生殖组织的发育。除了SEU，还有三个拟南芥seus - like （SLK）基因编码假定的转录接头。为了确定SLK基因的功能，并研究SEU和SLK基因之间的功能冗余程度，我们对拟南芥中可用的SLK突变系进行了表征。在这里，我们发现任何单个SLK基因的突变都不能导致明显的形态异常。然而，通过产生高阶突变植株，我们发现SLK基因之间以及SLK基因与SEU之间存在一定程度的冗余。我们报道了SEU和SLK基因在胚胎发育过程中的新作用，并表明SEU和SLK2活性的同时丧失会导致严重的胚胎和幼苗缺陷，其特征是茎尖分生组织的丧失。此外，我们证明了SLK基因功能对于来自心皮边缘的重要雌性生殖组织的正常发育是必需的。我们提出了一个模型，假设SEU和SLK基因通过两种不同的途径支持分生组织区域的器官发育：一种途径促进生长素反应，从而促进器官形成；另一种途径通过维持SHOOTMERISTEM-LESS和PHABULOSA的表达来维持分生组织的潜力。
Multimeric protein complexes are required during development to regulate transcription and orchestrate cellular proliferation and differentiation. The Arabidopsis (Arabidopsis thaliana) SEUSS (SEU) gene encodes a transcriptional adaptor that shares sequence similarity with metazoan Lim domain-binding transcriptional adaptors. In Arabidopsis, SEU forms a physical complex with the LEUNIG transcriptional coregulator. This complex regulates a number of diverse developmental events, including proper specification of floral organ identity and number and the development of female reproductive tissues derived from the carpel margin meristem. In addition to SEU, there are three Arabidopsis SEUSS-LIKE (SLK) genes that encode putative transcriptional adaptors. To determine the functions of the SLK genes and to investigate the degree of functional redundancy between SEU and SLK genes, we characterized available slk mutant lines in Arabidopsis. Here, we show that mutations in any single SLK gene failed to condition an obvious morphological abnormality. However, by generating higher order mutant plants, we uncovered a degree of redundancy between the SLK genes and between SLK genes and SEU. We report a novel role for SEU and the SLK genes during embryonic development and show that the concomitant loss of both SEU and SLK2 activities conditions severe embryonic and seedling defects characterized by a loss of the shoot apical meristem. Furthermore, we demonstrate that SLK gene function is required for proper development of vital female reproductive tissues derived from the carpel margin. We propose a model that posits that SEU and SLK genes support organ development from meristematic regions through two different pathways: one that facilitates auxin response and thus organ initiation and a second that sustains meristematic potential through the maintenance of SHOOTMERISTEM-LESS and PHABULOSA expression.