Coordinated Transcriptional Regulation by the UV-B Photoreceptor and Multiple Transcription Factors for Plant UV-B Responses
Coordinated Transcriptional Regulation by the UV-B Photoreceptor and Multiple Transcription Factors for Plant UV-B Responses
复制标题
UV-B 光感受器和多种转录因子对植物 UV-B 响应的协调转录调控
DOI：
10.1016/j.molp.2020.02.015
复制
发表时间：
2020-05-04
期刊：
影响因子：
27.5
通讯作者：
Huang, Xi
中科院分区：
文献类型：
--
作者：
Qian, Chongzhen;Chen, Zhiren;Huang, Xi
非损伤性紫外B（UV-B）光通过UV-B特异性信号转导促进拟南芥的光形态发生发育和胁迫驯化。UV-B辐射诱导UV-B光感受器UV抗性基因座8（UVR 8）的单体化和核移位。然而，目前尚不清楚UVR 8的核定位如何导致全局基因表达的变化。在这里，我们揭示了核UVR 8与几个先前已知的转录因子，包括伸长下胚轴5（HY 5）和植物色素相互作用因子4（PIF 4）一起管理UV-B响应转录网络。基于转录组学分析，我们确定MYB 13是UV-B诱导的子叶扩展和胁迫驯化的一个新的正调控因子。MYB 13是UV-B诱导的，并且主要在子叶中表达。我们的研究结果表明，MYB 13蛋白作为一个转录因子的功能，调节基因的表达参与生长素反应和黄酮类化合物的生物合成，通过直接结合其启动子。此外，光活化的UVR 8以UV-B依赖性方式与MYB 13相互作用，并差异性地调节MYB 13与其靶标的亲和力。总之，我们的研究结果阐明了UV-B光感受器UVR 8与细胞核中的各种转录因子的合作功能，以协调特定的下游基因组的表达，并最终介导植物对UV-B光的响应。
Non-damaging ultraviolet B (UV-B) light promotes photomorphogenic development and stress acclimation through UV-B-specific signal transduction in Arabidopsis. UV-B irradiation induces monomerization and nuclear translocation of the UV-B photoreceptor UV RESISTANCE LOCUS 8 (UVR8). However, it is not clear how the nuclear localization of UVR8 leads to changes in global gene expression. Here, we reveal that nuclear UVR8 governs UV-B-responsive transcriptional networks in concert with several previously known transcription factors, including ELONGATED HYPOCOTYL 5 (HY5) and PHYTOCHROME INTERACTING FACTOR 4 (PIF4). Based on the transcriptomic analysis, we identify MYB13 as a novel positive regulator in UV-B-induced cotyledon expansion and stress acclimation. MYB13 is UV-B inducible and is predominantly expressed in the cotyledons. Our results demonstrate that MYB13 protein functions as a transcription factor to regulate the expression of genes involved in auxin response and flavonoid biosynthesis through direct binding with their promoters. In addition, photoactivated UVR8 interacts with MYB13 in a UV-B-dependent manner and differentially modulates the affinity of MYB13 with its targets. Taken together, our results elucidate the cooperative function of the UV-B photoreceptor UVR8 with various transcription factors in the nucleus to orchestrate the expression of specific sets of downstream genes and, ultimately, mediate plant responses to UV-B light.