中科院植物所揭示lncRNA调节蒺藜苜蓿磷缺乏响应的分子机制

近来研究表明长非编码RNA（lncRNA）在许多生物过程中起着重要调控作用。在自然和农业生态系统中，普遍存在土壤无机磷（Pi）缺乏而抑制植物生长的现象；然而，目前对植物lncRNA在缺磷响应中的功能知之甚少。近日，中国科学院植物研究所植被与环境变化国家重点实验室张文浩研究组揭示lncRNA在调节豆科模式植物蒺藜苜蓿磷缺乏响应中具有重要作用。研究结果于2017年11月20日在线发表于《Journal of Experimental Botany》。

为寻找解决办法，研究人员对豆科植物蒺藜苜蓿（Medicago truncatula）8个链特异性文库进行测序，鉴定出10785个lncRNA。其中，响应叶和根中Pi缺乏的分别有358个和224个lncRNA。进一步对这些lncRNA的靶基因进行预测和分类，发现它们可能参与信号转导、能量合成、脱毒和Pi运输过程。此外，研究人员利用Tnt1突变体对3个磷酸盐缺乏诱导的lncRNA（PDIL）进行了功能研究。结果显示，PDIL1可抑制MtPHO2降解，MtPHO2编码一个由miR399调控的泛素缀合酶E2，而PDIL2和PDIL3则在转录水平调控Pi运输。以上结果表明，PDIL可调节磷缺乏信号及磷运输，揭示lncRNA在调节植物磷缺乏响应中具有重要作用。（来源：生物360）

Novel phosphate deficiency-responsive long non-coding RNAs in the legume model plant Medicago truncatula

Abstract Emerging evidence indicates that long non-coding RNAs (lncRNAs) play important roles in the regulation of many biological processes. Inhibition of plant growth due to deficiency in soil inorganic phosphate (Pi) occurs widely across natural and agricultural ecosystems; however, we know little about the function of plant lncRNAs in response to Pi deficiency. To address this issue, we first identified 10 785 lncRNAs in the legume model species Medicago truncatula by sequencing eight strand-specific libraries. Out of these lncRNAs, 358 and 224 were responsive to Pi deficiency in the leaves and roots, respectively. We further predicted and classified the putative targets of those lncRNAs and the results revealed that they may be involved in the processes of signal transduction, energy synthesis, detoxification, and Pi transport. Finally, we functionally characterized three Phosphate Deficiency-Induced LncRNAs (PDILs) using their corresponding Tnt1 mutants. The results showed that PDIL1 suppressed degradation of MtPHO2, which encodes a ubiquitin-conjugating E2 enzyme regulated by miR399, while PDIL2 and PDIL3 directly regulated Pi transport at the transcriptional level. These findings demonstrate that PDILs can regulate Pi-deficiency signaling and Pi transport, highlighting the involvement of lncRNAs in the regulation of responses of plants to Pi deficiency.

原文链接：https://academic.oup.com/jxb/advance-article/doi/10.1093/jxb/erx384/4641844?searchresult=1