title: Elevation of arginine decarboxylase-dependent putrescine production enhances aluminum tolerance by decreasing aluminum retention in root cell walls of wheat.
abstract: Aluminum (Al) stress induces putrescine (Put) accumulation in several plants and this response is proposed to alleviate Al toxicity. However, the mechanisms underlying this alleviation remain largely unknown. Here, we show that exposure to Al clearly increases Put accumulation in the roots of wheat plants (Triticum aestivum L. 'Xi Aimai-1') and that this was accompanied by significant increase in the activity of arginine decarboxylase (ADC), a Put producing enzyme. Application of an ADC inhibitor (d-arginine) terminated the Al-induced Put accumulation, indicating that increased ADC activity may be responsible for the increase in Put accumulation in response to Al. The d-arginine treatment also increased the Al-induced accumulation of cell wall polysaccharides and the degree of pectin demethylation in wheat roots. Thus, it elevated Al retention in cell walls and exacerbated Al accumulation in roots, both of which aggravate Al toxicity in wheat plants. The opposite effects were true for exogenous Put application. These results suggest that ADC-dependent Put accumulation plays important roles in providing protection against Al toxicity in wheat plants through decreasing cell wall polysaccharides and increasing the degree of pectin methylation, thus decreasing Al retention in the cell walls.
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: MOE Key Laboratory of Environment Remediation and Ecological Health, College of Natural Resource & Environmental Sciences, Zhejiang University, Hangzhou 310058, China; 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: Chongwei
authors.initials: C
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: Chengliang
authors.initials: C
authors.lastname: Sun
authors.affiliation: Montverde Academy, Shanghai 201702, China.
authors.forename: Jinghong
authors.initials: J
authors.lastname: Wang
authors.affiliation: MOE Key Laboratory of Environment Remediation and Ecological Health, College of Natural Resource & Environmental Sciences, Zhejiang University, Hangzhou 310058, China.
authors.forename: Yiquan
authors.initials: Y
authors.lastname: Ye
authors.affiliation: MOE Key Laboratory of Environment Remediation and Ecological Health, College of Natural Resource & Environmental Sciences, Zhejiang University, Hangzhou 310058, China; 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: Lingli
authors.initials: L
authors.lastname: Lu
authors.affiliation: MOE Key Laboratory of Environment Remediation and Ecological Health, College of Natural Resource & Environmental Sciences, Zhejiang University, Hangzhou 310058, China; Key Laboratory of Subtropical Soil Science and Plant Nutrition of Zhejiang Province, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, PR China. Electronic address: xylin@zju.edu.cn.
authors.forename: Xianyong
authors.initials: X
authors.lastname: Lin
mesh_terms: D000222:Adaptation, Physiological; D000535:Aluminum / Q000378:metabolism / Q000633:toxicity*; D002262:Carboxy-Lyases / Q000378:metabolism*; D002473:Cell Wall / Q000187:drug effects* / Q000378:metabolism; D002851:Chromatography, High Pressure Liquid; D018517:Plant Roots / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D011700:Putrescine / Q000096:biosynthesis*; D014908:Triticum / Q000201:enzymology / Q000378:metabolism*
chemical_list: D000535:Aluminum; D002262:Carboxy-Lyases; C019722:arginine decarboxylase; D011700:Putrescine
keywords: Aluminum tolerance; Arginine decarboxylase; Cell wall; Polyamine; Wheat