title: Exogenous Melatonin Improves Plant Iron Deficiency Tolerance via Increased Accumulation of Polyamine-Mediated Nitric Oxide.
abstract: Melatonin has recently been demonstrated to play important roles in the regulation of plant growth, development, and abiotic and biotic stress responses. However, the possible involvement of melatonin in Fe deficiency responses and the underlying mechanisms remained elusive inArabidopsis thaliana. In this study, Fe deficiency quickly induced melatonin synthesis inArabidopsisplants. Exogenous melatonin significantly increased the soluble Fe content of shoots and roots, and decreased the levels of root cell wall Fe bound to pectin and hemicellulose, thus alleviating Fe deficiency-induced chlorosis. Intriguingly, melatonin treatments induced a significant increase of nitric oxide (NO) accumulation in roots of Fe-deficient plants, but not in those of polyamine-deficient (adc2-1and d-arginine-treated) plants. Moreover, the melatonin-alleviated leaf chlorosis was blocked in the polyamine- and NO-deficient (nia1nia2noa1and c-PTIO-treated) plants, and the melatonin-induced Fe remobilization was largely inhibited. In addition, the expression of some Fe acquisition-related genes, includingFIT1,FRO2, andIRT1were significantly up-regulated by melatonin treatments, whereas the enhanced expression of these genes was obviously suppressed in the polyamine- and NO-deficient plants. Collectively, our results provide evidence to support the view that melatonin can increase the tolerance of plants to Fe deficiency in a process dependent on the polyamine-induced NO production under Fe-deficient conditions.
authors: School of Life Science and Technology, Tongji University, Shanghai 200092, China. czhou1224@hotmail.com.|Key Laboratory of Bio-organic Fertilizer Creation, Ministry of Agriculture, Anhui Science and Technology University, Bengbu 233100, China. czhou1224@hotmail.com.
authors: Cheng
authors: C
authors: Zhou
authors: School of Life Science and Technology, Tongji University, Shanghai 200092, China. liuzhikakashi@163.com.
authors: Zhi
authors: Z
authors: Liu
authors: School of Life Science and Technology, Tongji University, Shanghai 200092, China. putaojiuvsduyao@126.com.
authors: Lin
authors: L
authors: Zhu
authors: Key Laboratory of Bio-organic Fertilizer Creation, Ministry of Agriculture, Anhui Science and Technology University, Bengbu 233100, China. mazy@ahstu.edu.cn.
authors: Zhongyou
authors: Z
authors: Ma
authors: Key Laboratory of Bio-organic Fertilizer Creation, Ministry of Agriculture, Anhui Science and Technology University, Bengbu 233100, China. jfwang1@aliyun.com.
authors: Jianfei
authors: J
authors: Wang
authors: School of Life Science and Technology, Tongji University, Shanghai 200092, China. zhujian1@tongji.edu.cn.
authors: Jian
authors: J
authors: Zhu
mesh_terms: D017360:Arabidopsis / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000096:biosynthesis; D051792:Basic Helix-Loop-Helix Proteins / Q000096:biosynthesis; D027682:Cation Transport Proteins / Q000096:biosynthesis; D038181:FMN Reductase / Q000096:biosynthesis; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D007501:Iron / Q000378:metabolism*; D000090463:Iron Deficiencies; D008550:Melatonin / Q000378:metabolism* / Q000494:pharmacology; D009569:Nitric Oxide / Q000378:metabolism*; D018517:Plant Roots / Q000235:genetics / Q000254:growth & development / Q000378:metabolism; D018520:Plant Shoots / Q000235:genetics / Q000254:growth & development / Q000378:metabolism
chemical_list: D029681:Arabidopsis Proteins; D051792:Basic Helix-Loop-Helix Proteins; D027682:Cation Transport Proteins; D038181:FMN Reductase; D007501:Iron; D008550:Melatonin; D009569:Nitric Oxide; C501411:FIT1 protein, Arabidopsis; C099651:IRT1 protein, Arabidopsis; C023903:ferric citrate iron reductase
keywords: iron deficiency; iron remobilization; melatonin; nitric oxide (NO); polyamine