title: Expression of tobacco ethylene receptor NTHK1 alters plant responses to salt stress.
abstract: Ethylene has been regarded as a stress hormone involved in many stress responses. However, ethylene receptors have not been studied for the roles they played under salt stress condition. Previously, we characterized an ethylene receptor gene NTHK1 from tobacco, and found that NTHK1 is salt-inducible. Here, we report a further investigation towards the function of NTHK1 in response to salt stress by using a transgenic approach. We found that NTHK1 promotes leaf growth in the transgenic tobacco seedlings but affects salt sensitivity in these transgenic seedlings under salt stress condition. Differential Na+/K+ ratio was observed in the control Xanthi and NTHK1-transgenic plants after salt stress treatment. We further found that the NTHK1 transgene is also salt-inducible in the transgenic plants, and the higher NTHK1 expression results in early inductions of the ACC (1-aminocyclopropane-1-carboxylic acid) oxidase gene NtACO3 and ethylene responsive factor (ERF) genes NtERF1 and NtERF4 under salt stress. However, NTHK1 suppresses the salt-inducible expression of the ACC synthase gene NtACS1. These results indicate that NTHK1 regulates salt stress responses by affecting ion accumulation and related gene expressions, and hence have significance in elucidation of ethylene receptor functions during stress signal transduction.
authors.affiliation: National Key Laboratory of Plant Genomics, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, China.
authors.forename: Wan-Hong
authors.initials: WH
authors.lastname: Cao
authors.forename: Jun
authors.initials: J
authors.lastname: Liu
authors.forename: Qi-Yun
authors.initials: QY
authors.lastname: Zhou
authors.forename: Yang-Rong
authors.initials: YR
authors.lastname: Cao
authors.forename: Shu-Fang
authors.initials: SF
authors.lastname: Zheng
authors.forename: Bao-Xing
authors.initials: BX
authors.lastname: Du
authors.forename: Jin-Song
authors.initials: JS
authors.lastname: Zhang
authors.forename: Shou-Yi
authors.initials: SY
authors.lastname: Chen
mesh_terms: D005030:Ethylenes / Q000096:biosynthesis; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D017343:Genes, Plant / Q000235:genetics; D010641:Phenotype; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism*; D030821:Plants, Genetically Modified; D011188:Potassium / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D011956:Receptors, Cell Surface / Q000235:genetics / Q000378:metabolism*; D012964:Sodium / Q000378:metabolism; D012965:Sodium Chloride / Q000494:pharmacology*; D014026:Nicotiana / Q000187:drug effects* / Q000235:genetics / Q000378:metabolism*; D019076:Transgenes
chemical_list: D005030:Ethylenes; D010940:Plant Proteins; D012333:RNA, Messenger; D011956:Receptors, Cell Surface; C083750:ethylene receptors, plant; D012965:Sodium Chloride; C036216:ethylene; D012964:Sodium; D011188:Potassium