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Induction of root Fe(lll) reductase activity and proton extrusion by iron deficiency is mediated by auxin-based systemic signalling in Malus xiaojinensis

Iron is a critical cofactor for a number of metalloenzymes involved in respiration and photosynthesis, but plants often suffer from iron deficiency due to limited supplies of soluble iron in the soil. Iron deficiency induces a series of adaptive responses in various plant species, but the mechanisms...

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Autores principales: Wu, Ting, Zhang, Heng-Tao, Wang, Yi, Jia, Wen-Suo, Xu, Xue-Feng, Zhang, Xin-Zhong, Han, Zhen Hai
Formato: Online Artículo Texto
Lenguaje:English
Publicado: Oxford University Press 2012
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3254686/
https://www.ncbi.nlm.nih.gov/pubmed/22058407
http://dx.doi.org/10.1093/jxb/err314
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author Wu, Ting
Zhang, Heng-Tao
Wang, Yi
Jia, Wen-Suo
Xu, Xue-Feng
Zhang, Xin-Zhong
Han, Zhen Hai
author_facet Wu, Ting
Zhang, Heng-Tao
Wang, Yi
Jia, Wen-Suo
Xu, Xue-Feng
Zhang, Xin-Zhong
Han, Zhen Hai
author_sort Wu, Ting
collection PubMed
description Iron is a critical cofactor for a number of metalloenzymes involved in respiration and photosynthesis, but plants often suffer from iron deficiency due to limited supplies of soluble iron in the soil. Iron deficiency induces a series of adaptive responses in various plant species, but the mechanisms by which they are triggered remain largely unknown. Using pH imaging and hormone localization techniques, it has been demonstrated here that root Fe(III) reductase activity and proton extrusion upon iron deficiency are up-regulated by systemic auxin signalling in a Fe-efficient woody plant, Malus xiaojinensis. Split-root experiments demonstrated that Fe-deprivation in a portion of the root system induced a dramatic increase in Fe(III) reductase activity and proton extrusion in the Fe-supplied portion, suggesting that the iron deficiency responses were mediated by a systemic signalling. Reciprocal grafting experiments of M. xiaojinensis with Malus baccata, a plant with no capability to produce the corresponding responses, indicate that the initiation of the systemic signalling is likely to be determined by roots rather than shoots. Iron deficiency induced a substantial increase in the IAA content in the shoot apex and supplying exogenous IAA analogues (NAA) to the shoot apex could mimic the iron deficiency to trigger the corresponding responses. Conversely, preventing IAA transport from shoot to roots blocked the iron deficiency responses. These results strongly indicate that the iron deficiency-induced physiological responses are mediated by systemic auxin signalling.
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spelling pubmed-32546862012-01-11 Induction of root Fe(lll) reductase activity and proton extrusion by iron deficiency is mediated by auxin-based systemic signalling in Malus xiaojinensis Wu, Ting Zhang, Heng-Tao Wang, Yi Jia, Wen-Suo Xu, Xue-Feng Zhang, Xin-Zhong Han, Zhen Hai J Exp Bot Research Papers Iron is a critical cofactor for a number of metalloenzymes involved in respiration and photosynthesis, but plants often suffer from iron deficiency due to limited supplies of soluble iron in the soil. Iron deficiency induces a series of adaptive responses in various plant species, but the mechanisms by which they are triggered remain largely unknown. Using pH imaging and hormone localization techniques, it has been demonstrated here that root Fe(III) reductase activity and proton extrusion upon iron deficiency are up-regulated by systemic auxin signalling in a Fe-efficient woody plant, Malus xiaojinensis. Split-root experiments demonstrated that Fe-deprivation in a portion of the root system induced a dramatic increase in Fe(III) reductase activity and proton extrusion in the Fe-supplied portion, suggesting that the iron deficiency responses were mediated by a systemic signalling. Reciprocal grafting experiments of M. xiaojinensis with Malus baccata, a plant with no capability to produce the corresponding responses, indicate that the initiation of the systemic signalling is likely to be determined by roots rather than shoots. Iron deficiency induced a substantial increase in the IAA content in the shoot apex and supplying exogenous IAA analogues (NAA) to the shoot apex could mimic the iron deficiency to trigger the corresponding responses. Conversely, preventing IAA transport from shoot to roots blocked the iron deficiency responses. These results strongly indicate that the iron deficiency-induced physiological responses are mediated by systemic auxin signalling. Oxford University Press 2012-01 2011-11-04 /pmc/articles/PMC3254686/ /pubmed/22058407 http://dx.doi.org/10.1093/jxb/err314 Text en © 2011 The Author(s). This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/3.0), which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited. This paper is available online free of all access charges (see http://jxb.oxfordjournals.org/open_access.html for further details)
spellingShingle Research Papers
Wu, Ting
Zhang, Heng-Tao
Wang, Yi
Jia, Wen-Suo
Xu, Xue-Feng
Zhang, Xin-Zhong
Han, Zhen Hai
Induction of root Fe(lll) reductase activity and proton extrusion by iron deficiency is mediated by auxin-based systemic signalling in Malus xiaojinensis
title Induction of root Fe(lll) reductase activity and proton extrusion by iron deficiency is mediated by auxin-based systemic signalling in Malus xiaojinensis
title_full Induction of root Fe(lll) reductase activity and proton extrusion by iron deficiency is mediated by auxin-based systemic signalling in Malus xiaojinensis
title_fullStr Induction of root Fe(lll) reductase activity and proton extrusion by iron deficiency is mediated by auxin-based systemic signalling in Malus xiaojinensis
title_full_unstemmed Induction of root Fe(lll) reductase activity and proton extrusion by iron deficiency is mediated by auxin-based systemic signalling in Malus xiaojinensis
title_short Induction of root Fe(lll) reductase activity and proton extrusion by iron deficiency is mediated by auxin-based systemic signalling in Malus xiaojinensis
title_sort induction of root fe(lll) reductase activity and proton extrusion by iron deficiency is mediated by auxin-based systemic signalling in malus xiaojinensis
topic Research Papers
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3254686/
https://www.ncbi.nlm.nih.gov/pubmed/22058407
http://dx.doi.org/10.1093/jxb/err314
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