title: The nitrate transporter NRT2.1 functions in the ethylene response to nitrate deficiency in Arabidopsis.
abstract: The ethylene signalling pathway is closely associated with complex environmental stresses. Previous studies have reported impact of high nitrate (HN) availability on ethylene biosynthesis and regulation of ethylene on nitrate transporter 2.1 (NRT2.1) expression. However, molecular interaction between NRT2.1 transcript levels and the ethylene signalling pathway under nitrate deficiency is still elusive. Here, we report a low nitrate (LN) treatment-induced rapid burst of ethylene production and regulated expression of ethylene signalling components CTR1, EIN3 and EIL1 in wild-type Arabidopsis thaliana (Col-0) seedlings, and enhanced ethylene response reporter EBS:GUS activity in both Col-0 and the ethylene mutants ein3-1eil1-1 and ctr1-1. LN treatment also caused up-regulation of NRT2.1 expression, which was responsible for an enhanced high-affinity nitrate uptake. Comparison of ethylene production and EBS:GUS activity between nrt1.1, nrt2.1 mutants and Col-0 indicated that this up-regulation of NRT2.1 expression caused a positive effect on ethylene biosynthesis and signalling under LN treatment. On the other hand, ethylene down-regulated NRT2.1 expression and reduced the high-affinity nitrate uptake. Together, these findings uncover a negative feedback loop between NRT2.1 expression and ethylene biosynthesis and signalling under nitrate deficiency, which may contribute to finely tuning of plant nitrate acquisition during exploring dynamic soil conditions.
authors.affiliation: College of Biological Sciences and Technology, National Engineering Laboratory for Tree Breeding, Beijing Forestry University, No. 35, Qinghua East Road, Beijing 100083, China.
authors.forename: Dongchao
authors.initials: D
authors.lastname: Zheng
authors.affiliation: College of Biological Sciences and Technology, National Engineering Laboratory for Tree Breeding, Beijing Forestry University, No. 35, Qinghua East Road, Beijing, 100083, China.
authors.forename: Xiao
authors.initials: X
authors.lastname: Han
authors.affiliation: College of Biological Sciences and Technology, National Engineering Laboratory for Tree Breeding, Beijing Forestry University, No. 35, Qinghua East Road, Beijing, 100083, China.
authors.forename: Y I
authors.initials: YI
authors.lastname: An
authors.affiliation: State Key Laboratory of Protein and Plant Gene Research, College of Life Sciences, Peking-Tsinghua Center for Life Sciences, Peking University, Beijing, 100871, China.
authors.forename: Hongwei
authors.initials: H
authors.lastname: Guo
authors.affiliation: College of Biological Sciences and Technology, National Engineering Laboratory for Tree Breeding, Beijing Forestry University, No. 35, Qinghua East Road, Beijing, 100083, China.
authors.forename: Xinli
authors.initials: X
authors.lastname: Xia
authors.affiliation: College of Biological Sciences and Technology, National Engineering Laboratory for Tree Breeding, Beijing Forestry University, No. 35, Qinghua East Road, Beijing, 100083, China.
authors.forename: Weilun
authors.initials: W
authors.lastname: Yin
mesh_terms: D027321:Anion Transport Proteins / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D017360:Arabidopsis / Q000187:drug effects / Q000235:genetics / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D005030:Ethylenes / Q000096:biosynthesis / Q000378:metabolism*; D018506:Gene Expression Regulation, Plant; D009566:Nitrates / Q000378:metabolism*; D010937:Plant Growth Regulators / Q000096:biosynthesis / Q000378:metabolism*; D015398:Signal Transduction / Q000187:drug effects
chemical_list: D027321:Anion Transport Proteins; D029681:Arabidopsis Proteins; D005030:Ethylenes; D009566:Nitrates; D010937:Plant Growth Regulators; C477335:NRT2.1 protein, Arabidopsis; C036216:ethylene
keywords: ethylene biosynthesis and signalling; high-affinity transport system; low nitrate