Journal
PLANT PHYSIOLOGY
Volume 168, Issue 1, Pages 258-U473Publisher
OXFORD UNIV PRESS INC
DOI: 10.1104/pp.114.254672
Keywords
-
Categories
Funding
- Spanish Ministry of Economy and Competitiveness [AGL-2012-32974]
- Formacion del Personal Investigador fellowship [BES-2013-062674]
- Marie Curie International Reintegration grant [IRG-2010-276771]
- European Research Council [ERC-2013-StG-335284]
- Ramon y Cajal fellowship [RYC-2010-06363]
- Direct For Biological Sciences
- Division Of Integrative Organismal Systems [1127155] Funding Source: National Science Foundation
Ask authors/readers for more resources
Iron is critical for symbiotic nitrogen fixation (SNF) as a key component ofmultiple ferroproteins involved in this biological process. In the model legume Medicago truncatula, iron is delivered by the vasculature to the infection/maturation zone (zone II) of the nodule, where it is released to the apoplast. From there, plasma membrane iron transporters move it into rhizobia-containing cells, where iron is used as the cofactor of multiple plant and rhizobial proteins (e.g. plant leghemoglobin and bacterial nitrogenase). MtNramp1 (Medtr3g088460) is the M. truncatula Natural Resistance-Associated Macrophage Protein family member, with the highest expression levels in roots and nodules. Immunolocalization studies indicate that MtNramp1 is mainly targeted to the plasma membrane. A loss-of-function nramp1 mutant exhibited reduced growth compared with the wild type under symbiotic conditions, but not when fertilized with mineral nitrogen. Nitrogenase activity was low in the mutant, whereas exogenous iron and expression of wild-type MtNramp1 in mutant nodules increased nitrogen fixation to normal levels. These data are consistent with a model in which MtNramp1 is the main transporter responsible for apoplastic iron uptake by rhizobia-infected cells in zone II.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available