Orchestration of Processing Body Dynamics and mRNA Decay in Arabidopsis Immunity.
Orchestration of Processing Body Dynamics and mRNA Decay in Arabidopsis Immunity.
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DOI：
10.1016/j.celrep.2019.07.054
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发表时间：
2019-08
期刊：
影响因子：
8.8
通讯作者：
Xiao Yu;Bo Li;Geng-Jen Jang;Shan Jiang;D. Jiāng;Jyan-Chyun Jang;Shu-Hsing Wu;Libo Shan;P. He
中科院分区：
文献类型：
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作者：
Xiao Yu;Bo Li;Geng-Jen Jang;Shan Jiang;D. Jiāng;Jyan-Chyun Jang;Shu-Hsing Wu;Libo Shan;P. He
适当的转录组重新编程对于宿主在病原体攻击时发起有效的防御反应至关重要。免疫相关基因是如何在转录后水平上进行调控的，目前尚不清楚。我们在这里证明了P-小体，与5‘-到-3’mRNA衰变相关的非膜性细胞质核糖核蛋白焦点，在由微生物相关分子模式(MAMPs)触发的植物免疫中受到动态调节。DCP1-DCP2信使核糖核酸解离复合体是P小体的标志，对植物MAMP触发的反应和对病原菌的免疫具有积极的调节作用。MAMP激活的MAP激酶直接磷酸化丝氨酸237残基上的DCP1，从而进一步刺激其与XRN4的相互作用，XRN4是一种执行去帽基因5‘-3’降解的核酸外切酶。因此，MAMP处理加强了一组特定的MAMP下调基因上依赖于DCP1的mRNA的衰退。因此，由MAMP激活的MAP激酶级联所引起的保守的5‘-to-3’m RNA衰变是植物免疫的一个组成部分。这一机制确保了某些免疫相关基因的转录后快速下调，否则可能会对免疫产生负面影响。
Proper transcriptome reprogramming is critical for hosts to launch an effective defense response upon pathogen attack. How immune-related genes are regulated at the posttranscriptional level remains elusive. We demonstrate here that P-bodies, the non-membranous cytoplasmic ribonucleoprotein foci related to 5′-to-3′ mRNA decay, are dynamically modulated in plant immunity triggered by microbe-associated molecular patterns (MAMPs). The DCP1-DCP2 mRNA decapping complex, a hallmark of P-bodies, positively regulates plant MAMP-triggered responses and immunity against pathogenic bacteria. MAMP-activated MAP kinases directly phosphorylate DCP1 at the serine237residue, which further stimulates its interaction with XRN4, an exonuclease executing 5′-to-3′ degradation of decapped mRNA. Consequently, MAMP treatment potentiates DCP1-dependent mRNA decay on a specific group of MAMP-downregulated genes. Thus, the conserved 5′-to-3′ mRNA decay elicited by the MAMP-activated MAP kinase cascade is an integral part of plant immunity. This mechanism ensures a rapid posttranscriptional downregulation of certain immune-related genes that may otherwise negatively impact immunity.