title: Elevation of NO production increases Fe immobilization in the Fe-deficiency roots apoplast by decreasing pectin methylation of cell wall.
abstract: Cell wall is the major component of root apoplast which is the main reservoir for iron in roots, while nitric oxide (NO) is involved in regulating the synthesis of cell wall. However, whether such regulation could influence the reutilization of iron stored in root apoplast remains unclear. In this study, we observed that iron deficiency elevated NO level in tomato (Solanum lycopersicum) roots. However, application of S-nitrosoglutathione, a NO donor, significantly enhanced iron retention in root apoplast of iron-deficient plants, accompanied with a decrease of iron level in xylem sap. Consequently, S-nitrosoglutathione treatment increased iron concentration in roots, but decreased it in shoots. The opposite was true for the NO scavenging treatment with 2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide (cPTIO). Interestingly, S-nitrosoglutathione treatment increased pectin methylesterase activity and decreased degree of pectin methylation in root cell wall of both iron-deficient and iron-sufficient plants, which led to an increased iron retention in pectin fraction, thus increasing the binding capacity of iron to the extracted cell wall. Altogether, these results suggested that iron-deficiency-induced elevation of NO increases iron immobilization in root apoplast by decreasing pectin methylation in cell wall.
authors.affiliation: MOE Key Laboratory of Environment Remediation and Ecological Health, College of Natural Resource &Environmental Sciences, Zhejiang University, Hangzhou 310058, China.
authors.forename: Yi Quan
authors.initials: YQ
authors.lastname: Ye
authors.affiliation: 1] MOE Key Laboratory of Environment Remediation and Ecological Health, College of Natural Resource &Environmental Sciences, Zhejiang University, Hangzhou 310058, China [2] Key Laboratory of Subtropical Soil Science and Plant Nutrition of Zhejiang Province, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, PR China.
authors.forename: Chong Wei
authors.initials: CW
authors.lastname: Jin
authors.affiliation: MOE Key Laboratory of Environment Remediation and Ecological Health, College of Natural Resource &Environmental Sciences, Zhejiang University, Hangzhou 310058, China.
authors.forename: Shi Kai
authors.initials: SK
authors.lastname: Fan
authors.affiliation: MOE Key Laboratory of Environment Remediation and Ecological Health, College of Natural Resource &Environmental Sciences, Zhejiang University, Hangzhou 310058, China.
authors.forename: Qian Qian
authors.initials: QQ
authors.lastname: Mao
authors.affiliation: MOE Key Laboratory of Environment Remediation and Ecological Health, College of Natural Resource &Environmental Sciences, Zhejiang University, Hangzhou 310058, China.
authors.forename: Cheng Liang
authors.initials: CL
authors.lastname: Sun
authors.affiliation: MOE Key Laboratory of Environment Remediation and Ecological Health, College of Natural Resource &Environmental Sciences, Zhejiang University, Hangzhou 310058, China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Yu
authors.affiliation: 1] MOE Key Laboratory of Environment Remediation and Ecological Health, College of Natural Resource &Environmental Sciences, Zhejiang University, Hangzhou 310058, China [2] Key Laboratory of Subtropical Soil Science and Plant Nutrition of Zhejiang Province, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, PR China.
authors.forename: Xian Yong
authors.initials: XY
authors.lastname: Lin
mesh_terms: D001565:Benzoates / Q000494:pharmacology; D002265:Carboxylic Ester Hydrolases / Q000378:metabolism; D002473:Cell Wall / Q000187:drug effects* / Q000378:metabolism; D016166:Free Radical Scavengers / Q000494:pharmacology; D007093:Imidazoles / Q000494:pharmacology; D007501:Iron / Q000378:metabolism*; D018551:Solanum lycopersicum / Q000187:drug effects* / Q000378:metabolism; D009569:Nitric Oxide / Q000819:agonists / Q000037:antagonists & inhibitors / Q000096:biosynthesis*; D020030:Nitric Oxide Donors / Q000737:chemistry / Q000494:pharmacology; D010368:Pectins / Q000378:metabolism; D010940:Plant Proteins / Q000378:metabolism; D018517:Plant Roots / Q000187:drug effects* / Q000378:metabolism; D026422:S-Nitrosoglutathione / Q000737:chemistry* / Q000494:pharmacology; D052584:Xylem / Q000187:drug effects / Q000378:metabolism
chemical_list: D001565:Benzoates; D016166:Free Radical Scavengers; D007093:Imidazoles; D020030:Nitric Oxide Donors; D010940:Plant Proteins; C079393:1,3-dihydroxy-4,4,5,5-tetramethyl-2-(4-carboxyphenyl)tetrahydroimidazole; D009569:Nitric Oxide; D026422:S-Nitrosoglutathione; D010368:Pectins; D007501:Iron; D002265:Carboxylic Ester Hydrolases; C022323:pectinesterase