Plant lncRNAs are enriched in and move systemically through the phloem in response to phosphate deficiency  

作　　者：Zhaoliang Zhang Yi Zheng Byung-Kook Ham Shupei Zhang Zhangjun Fei William J.Lucas 

机构地区：[1]State Key Laboratory of Tea Biology and Utilization, Anhui Agricultural University [2]Boyce Thompson Institute for Plant Research, Cornell University [3]Global Institute for Food Security, Department of Biology, University of Saskatchewan [4]Department of Plant Biology, College of Biological Sciences, University of California

出　　处：《Journal of Integrative Plant Biology》2019年第4期492-508,共17页植物学报（英文版）

基　　金：supported by grants from the National Science Foundation(IOS-1339128 to W.J.L.);the National Natural Science Foundation of China(31770731to Z.Z.);Anhui Provincial the Department of Science and Technology(17030701049 to Z.Z.);the USDA National Institute of Food and Agriculture Specialty Crop Research Initiative(2015-51181-24285 to Z.F.)

摘　　要：In response to phosphate(Pi) deficiency, it has been shown that micro-RNAs(miRNAs) and mRNAs are transported through the phloem for delivery to sink tissues. Growing evidence also indicates that long noncoding RNAs(lncRNAs) are critical regulators of Pi homeostasis in plants. However, whether lncRNAs are present in and move through the phloem, in response to Pi deficiency, remains to be established. Here, using cucumber as a model plant, we show that lncRNAs are enriched in the phloem translocation stream and respond,systemically, to an imposed Pi-stress. A well-known lncRNA, IPS1, the target mimic(TM) of miRNA399,accumulates to a high level in the phloem, but is not responsive to early Pi deficiency. An additional 24 miRNA TMs were also detected in the phloem translocation stream; among them miRNA171 TMs and miR166 TMs were induced in response to an imposed Pi stress.Grafting studies identified 22 lncRNAs which move systemically into developing leaves and root tips. A CU-rich PTB motif was further identified in these mobile lncRNAs. Our findings revealed that lncRNAs respond to Pi deficiency, non-cell-autonomously, and may act as systemic signaling agents to coordinate early Pi deficiency signaling, at the whole-plant level.In response to phosphate(Pi) deficiency, it has been shown that micro-RNAs(miRNAs) and mRNAs are transported through the phloem for delivery to sink tissues. Growing evidence also indicates that long noncoding RNAs(lncRNAs) are critical regulators of Pi homeostasis in plants. However, whether lncRNAs are present in and move through the phloem, in response to Pi deficiency, remains to be established. Here, using cucumber as a model plant, we show that lncRNAs are enriched in the phloem translocation stream and respond,systemically, to an imposed Pi-stress. A well-known lncRNA, IPS1, the target mimic(TM) of miRNA399,accumulates to a high level in the phloem, but is not responsive to early Pi deficiency. An additional 24 miRNA TMs were also detected in the phloem translocation stream; among them miRNA171 TMs and miR166 TMs were induced in response to an imposed Pi stress.Grafting studies identified 22 lncRNAs which move systemically into developing leaves and root tips. A CU-rich PTB motif was further identified in these mobile lncRNAs. Our findings revealed that lncRNAs respond to Pi deficiency, non-cell-autonomously, and may act as systemic signaling agents to coordinate early Pi deficiency signaling, at the whole-plant level.

关 键 词：PLANT lncRNAs enriched PHLOEM PHOSPHATE DEFICIENCY 

分 类 号：Q[生物学]