FORCA, a promoter element that responds to crosstalk between defense and light signaling
FORCA, a promoter element that responds to crosstalk between defense and light signaling
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DOI：
10.1186/1471-2229-9-2
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发表时间：
2009-01-07
影响因子：
5.3
通讯作者：
Eulgem, Thomas
中科院分区：
文献类型：
--
作者：
Evrard, Alexandre;Ndatimana, Theogene;Eulgem, Thomas
背景：病原微生物识别触发植物全面的转录重编程。为了确定植物免疫反应所需的转录组水平的控制元件，我们正在研究几组基因的微阵列实验中发现的共激活的拟南芥（拟南芥）幼苗感染卵菌Hyaloperonospora寄生。在共表达基因簇中保守的启动子基序可能参与介导协调的基因活性模式。虽然许多研究确定了这样的保守的启动子基序在共表达的基因集，报告确认其功能的监管elements are rare.Results：FORCA是一个六聚体的启动子基序，是保守的拟南芥基因簇共表达的真菌或卵菌病原体，以及定义的光处理。FORCA通常比统计学预期更频繁地存在于拟南芥启动子区域中。它以DNA序列特异性的方式与拟南芥核蛋白质组成型相互作用。这些相互作用被防御相关的刺激所抑制，并通过长时间暴露于恒定的光而增强。此外，FORCA介导瞬时转化的本塞姆氏烟草叶以及稳定转化的拟南芥植物中的组成型报告基因表达。它对防御刺激的反应受光照时间的调节。在正常光照条件或恒定黑暗条件下生长的植物中，防御相关刺激导致FORCA介导的报告基因表达的抑制，而在恒定光照条件下生长的植物中，防御诱导导致FORCA介导的表达增强。此外，我们发现，植物受到持续的光暴露表现出降低的敏感性毒性H。结论：我们认为FORCA是一个存在于多种拟南芥启动子中的调控顺式元件。它整合了光和防御相关的信号，并参与调节转录组以适应环境条件的变化。
Background: Recognition of pathogenic microorganisms triggers in plants comprehensive transcriptional reprogramming. In order to identify transcriptome-level control elements required for plant immune responses we are examining several sets of genes found by microarray experiments to be co-activated in Arabidopsis thaliana (Arabidopsis) seedlings infected with the oomycete Hyaloperonospora parasitica. Promoter motifs conserved in clusters of co-expressed genes may be involved in mediating coordinated gene activity patterns. Although numerous studies identified such conserved promoter motifs in co-expressed gene sets, reports confirming their function as regulatory elements are rare.Results: FORCA is a hexameric promoter motif that is conserved in clusters of Arabidopsis genes co-expressed in response to fungal or oomycete pathogens as well as defined light treatments. FORCA is generally more frequently present in Arabidopsis promoter regions than statistically expected. It constitutively interacts in a DNA-sequence specific manner with nuclear Arabidopsis proteins. These interactions are suppressed by defense-related stimuli and enhanced by prolonged exposure to constant light. Furthermore FORCA mediates constitutive reporter gene expression in transiently transformed Nicotiana benthamiana leaves as well as in stably transformed Arabidopsis plants. Its responsiveness to defense-stimuli is modulated by the duration of light exposure. In plants grown under normal light conditions or constant darkness defense-related stimuli result in suppression of FORCA-mediated reporter gene expression, while in plants grown under constant light exposure, defense-induction results in enhanced FORCA-mediated expression. In addition, we found plants subjected to constant light exposure to exhibit reduced susceptibility to virulent H. parasitica.Conclusion: We propose that FORCA is a regulatory cis-element that is present in a wide variety of Arabidopsis promoters. It integrates light-and defense-related signals and participates in adjusting the transcriptome to changes in environmental conditions.