CREB-binding protein gene, HAC701, negatively regulates WRKY45-dependent immunity in rice
CREB-binding protein gene, HAC701, negatively regulates WRKY45-dependent immunity in rice
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DOI：
10.1101/2020.08.26.268797
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发表时间：
2020-08
期刊：
影响因子：
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通讯作者：
Nino A. Espinas;T. N. Le;Miura Saori;Yasuka Shimajiri;K. Shirasu;H. Saze
中科院分区：
文献类型：
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作者：
Nino A. Espinas;T. N. Le;Miura Saori;Yasuka Shimajiri;K. Shirasu;H. Saze
CREB结合蛋白(CBP)是一种已知的转录共激活因子和乙酰基转移酶，通过调节基因表达在多种细胞过程中发挥作用。然而，它如何在植物免疫中发挥作用仍未被探索。通过对HAC701的鉴定，我们证明了HAC701对水稻的免疫应答具有负性调节作用。Hac701对一种细菌病原体--丁香假单胞菌具有更强的抗病能力。水稻白粉病(Oryzae(PSO))引起水稻白叶枯病。我们的转录分析表明，水稻免疫的主要调节基因之一WRKY45在hac701中表达上调，可能与水稻对PSO的抗性表型有关。Hac701单一突变体的形态表型与以往报道的WRKY45过表达转基因品系高度相似。此外，我们还将这些研究中WRKY45过表达和化学诱导瞬时表达的基因列表与hac701中的差异表达基因(Degs)进行了比较，发现它们大部分重叠。当我们研究发现WRKY45基因上游1kb的顺式元件和WRKY45依赖的deGS时，我们发现WRKY45启动子含有Cre基序，这可能是HAC701介导的调控的靶点。全基因组H3K9乙酰化图谱显示hac701中大量基因的乙酰化缺失。然而，与WRKY45基因表达上调一致，我们的芯片测序分析表明，与模拟条件下分离的野生型对照相比，在hac701中WRKY45启动子的区域富含H3K9乙酰化。当HAC701这样的全球调控因子发生突变时，WRKY45启动子可能是可能的全基因组补偿效应的接收端。最后，我们证明了HAC701可能在系统免疫信号中起作用。因此，我们认为野生型HAC701负调控WRKY45基因的表达，从而抑制免疫反应。意义HAC701是CREB结合蛋白(CBP)家族中的一员，作为转录共激活因子和乙酰转移酶发挥作用。然而，人们对它如何调节植物的先天免疫知之甚少。在此，我们报道了水稻HAC701抑制WRKY45依赖的防御途径。我们的研究表明，在水稻中，HAC701似乎与WRKY45在遗传上相互作用，调节对病原体的免疫反应。
CREB-binding protein (CBP) is a known transcriptional coactivator and an acetyltransferase that functions in several cellular processes by regulating gene expression. However, how it functions in plant immunity remains unexplored. By characterizing hac701, we demonstrate that HAC701 negatively regulates the immune responses in rice. hac701 shows enhanced disease resistance against a bacterial pathogen, Pseudomonas syringae pv. oryzae (Pso), which causes bacterial halo blight of rice. Our transcriptomic analysis revealed that rice WRKY45, one of the main regulators of rice immunity, is upregulated in hac701 and possibly conferring the resistance phenotype against Pso. The morphological phenotypes of hac701 single mutants were highly similar to WRKY45 overexpression transgenic lines reported in previous studies. In addition, we also compared the list of genes in these studies when WRKY45 is overexpressed and chemically induced transiently with the differentially expressed genes (DEGs) in hac701, and found that they largely overlap. When we investigated for cis-elements found 1kb upstream of WRKY45 gene and WRKY45-dependent DEGs, we found that WRKY45 promoter contains the CRE motif, a possible target of HAC701-mediated regulation. Genome-wide H3K9 acetylation profiling showed depletion of acetylation at large set of genes in hac701. However, consistent with the upregulation of WRKY45 gene expression, our ChIP-sequencing analysis demonstrated that regions of WRKY45 promoter are enriched in H3K9 acetylation in hac701 compared to the segregated wild type control in the mock condition. WRKY45 promoter might be on the receiving end for possible genome-wide compensatory effects when a global regulator like HAC701 is mutated. Finally, we show that HAC701 may have roles in systemic immune signaling. We therefore propose that wild type HAC701 negatively regulates WRKY45 gene expression, thereby suppressing immune responses. SIGNIFICANCE HAC701 is a member of CREB-binding protein (CBP) family that acts as transcriptional coactivator and acetyltransferase. However, little is known how it regulates innate immunity in plants. Herein we reported that rice HAC701 suppresses WRKY45-dependent defense pathway. Our study showed that HAC701 seemingly interacts genetically with WRKY45 in rice to modulate immune responses against pathogens.