Auxin Response Regulators in Arabidopsis Embryogenesis

拟南芥胚胎发生中的生长素反应调节因子

• 批准号: 5371768
• 负责人: Professor Dr. Gerd Jürgens
• 金额: --
• 依托单位: Abteilung für Entwicklungsgenetik
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2001
• 资助国家: 德国
• 起止时间: 2000-12-31 至 2002-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/5371768?language=en
• 关键词: Auxin; Response; Regulators; Arabidopsis; Embryogenesis

The Arabidopsis genome encodes at least 20 IAA proteins involved in response to the plant hormone auxin. IAA proteins share four conserved domains, with domain II conferring protein instability. Domain III interacts with ARF transcription factors that regulate auxin-responsive target genes. It is unknown how specific effects are brought about by different IAA proteins. We have focused on the bodenlos (bdl) mutant which displays specific defects in early embryogenesis, due to an amino acid exchange in domain II of IAA12. By contrast, homologous mutations in six other IAA genes do not lead to defects in embryogenesis. The aim of this project is to analyse what determines the specificity of the bdl phenotype. We will express other IAA coding sequences with bdl-homologous (bdlh) mutations under the control of the BDL cis-regulatory sequences in transgenic Arabidopsis plants. If these transgenes can mimic the bdl phenotype developmental gene regulation would confer specificity of action. If, however, these transgenes can not mimic the bdl phenotype specificity of BDL action resides in its amino acid sequence. In the latter case, we will "swap" regions of BDL and other IAA proteins to identify the specificity determinat(s). BDL specificity domain(s) will be used to isolate specific interactors in the yeast two-hybrid system, followed by functional analyses.

拟南芥基因组编码至少20种IAA蛋白，参与对植物激素生长素的应答。IAA蛋白共有四个保守结构域，结构域II赋予蛋白质不稳定性。结构域III与调节生长素应答靶基因的ARF转录因子相互作用。目前还不清楚不同的IAA蛋白质如何产生特定的作用。我们已经集中在bodenlos（BDL）突变体显示特定的缺陷，在早期胚胎发生，由于IAA12的结构域II中的氨基酸交换。相比之下，其他六个IAA基因的同源突变不会导致胚胎发生缺陷。这个项目的目的是分析是什么决定了bdl表型的特异性。我们将在转基因拟南芥植物中表达在BDL顺式调控序列控制下具有BDL同源（bdlh）突变的其他IAA编码序列。如果这些转基因可以模拟bdl表型，发育基因调控将赋予作用的特异性。然而，如果这些转基因不能模拟BDL的表型特异性，BDL的作用就在于其氨基酸序列。在后一种情况下，我们将“交换”BDL和其他IAA蛋白的区域以鉴定特异性决定簇。BDL特异性结构域将用于分离酵母双杂交系统中的特异性相互作用物，然后进行功能分析。