Chen Jikang, Gao Gang, Chen Ping, Chen Kunmei, Wang Xiaofei, Bai Lianyang, Yu Chunming, Zhu Aiguo
Longping Branch, Graduate School of Hunan University, Changsha 410082, China.
Institute of Bast Fiber Crops, Chinese Academy of Agricultural Sciences, Changsha 410205, China.
Plants (Basel). 2020 Sep 25;9(10):1267. doi: 10.3390/plants9101267.
Water and N are the most important factors affecting ramie ( (L.) Gaudich) growth. In this study, de novo transcriptome assembly and Tandem Mass Tags (TMT) based quantitative proteome analysis of ramie under nitrogen and water co-limitation conditions were performed, and exposed to treatments, including drought and N-deficit (WdNd), proper water but N-deficit (WNd), proper N but drought (WdN), and proper N and water (CK), respectively. A total of 64,848 unigenes (41.92% of total unigenes) were annotated in at least one database, including NCBI non-redundant protein sequences (Nr), Swiss-Prot, Protein family (Pfam), Gene Ontology (GO) and KEGG Orthology (KO), and 4268 protein groups were identified. Most significant changes in transcript levels happened under water-limited conditions, but most significant changes in protein level happened under water-limited conditions only with proper N. Poor correlation between differentially expressed genes (DEGs) and differentially expressed proteins (DEPs) was observed in ramie responding to the treatments. DEG/DEP regulation patterns related to major metabolic processes responding to water and N deficiency were analyzed, including photosynthesis, ethylene responding, glycolysis, and nitrogen metabolism. Moreover, 41 DEGs and 61 DEPs involved in regulating adaptation of ramie under water and N stresses were provided in the study, including DEGs/DEPs related to UDP-glucuronosyhransferase (UGT), ATP synthase, and carbonate dehydratase. The strong dependency of N-response of ramie on water conditions at the gene and protein levels was highlighted. Advices for simultaneously improving water and N efficiency in ramie were also provided, especially in breeding N efficient varieties with drought resistance. This study provided extensive new information on the transcriptome, proteome, their correlation, and diversification in ramie responding to water and N co-limitation.
水和氮是影响苎麻（(L.) Gaudich）生长的最重要因素。在本研究中，对氮和水共同限制条件下的苎麻进行了从头转录组组装和基于串联质谱标签（TMT）的定量蛋白质组分析，并分别设置了干旱和缺氮（WdNd）、水分适宜但缺氮（WNd）、氮素适宜但干旱（WdN）以及氮和水均适宜（CK）的处理。共有64,848个单基因（占总单基因的41.92%）在至少一个数据库中得到注释，这些数据库包括NCBI非冗余蛋白质序列（Nr）、Swiss-Prot、蛋白质家族（Pfam）、基因本体论（GO）和KEGG直系同源基因（KO），共鉴定出4268个蛋白质组。转录水平的最显著变化发生在水分受限条件下，但蛋白质水平的最显著变化仅发生在氮素适宜的水分受限条件下。在苎麻对处理的响应中，观察到差异表达基因（DEG）和差异表达蛋白质（DEP）之间的相关性较差。分析了与响应水分和氮素缺乏的主要代谢过程相关的DEG/DEP调控模式，包括光合作用、乙烯响应、糖酵解和氮代谢。此外，本研究还提供了41个参与调控苎麻在水分和氮胁迫下适应性的DEG和61个DEP，包括与UDP-葡萄糖醛酸转移酶（UGT）、ATP合酶和碳酸酐酶相关的DEG/DEP。突出了苎麻在基因和蛋白质水平上对氮响应强烈依赖于水分条件的特点，并为同时提高苎麻的水分和氮效率提供了建议，特别是在培育具有抗旱性的氮高效品种方面。本研究提供了关于苎麻响应水和氮共同限制时的转录组、蛋白质组、它们的相关性以及多样性的广泛新信息。
