Journal article

Nitrogen assimilation system in maize is regulated by developmental and tissue-specific mechanisms

Darren Plett, Luke Holtham, Ute Baumann, Elena Kalashyan, Karen Francis, Akiko Enju, John Toubia, Ute Roessner, Antony Bacic, Antoni Rafalski, Kanwarpal S Dhugga, Mark Tester, Trevor Garnett, Brent N Kaiser



KEY MESSAGE: We found metabolites, enzyme activities and enzyme transcript abundances vary significantly across the maize lifecycle, but weak correlation exists between the three groups. We identified putative genes regulating nitrate assimilation. Progress in improving nitrogen (N) use efficiency (NUE) of crop plants has been hampered by the complexity of the N uptake and utilisation systems. To understand this complexity we measured the activities of seven enzymes and ten metabolites related to N metabolism in the leaf and root tissues of Gaspe Flint maize plants grown in 0.5 or 2.5 mM NO3 (-) throughout the lifecycle. The amino acids had remarkably similar profiles across the lifecycle ex..

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Awarded by Australian Council Linkage Grant

Funding Acknowledgements

The project was funded by the Australian Centre for Plant Functional Genomics, DuPont Pioneer, Australian Council Linkage Grant (LP0776635) to BNK, MT (University of Adelaide) and AR, KSD (DuPont Pioneer). The authors gratefully acknowledge the assistance of Lynne Fallis, Hari Kishan Rao Abbaraju, Vanessa Conn, Stephanie Feakin, Jaskaranbir Kaur, Simon Conn, Mary Beatty, and Kevin Hays. The authors also thank Ms Priyanka Reddy and Ms Chia Ng, Metabolomics Australia, School of BioSciences, The University of Melbourne, for sample preparation and amino acid analysis. UR and AB are also grateful to Victorian Node of Metabolomics Australia, which is funded through Bioplatforms Australia Pty Ltd, a National Collaborative Research Infrastructure Strategy (NCRIS), 5.1 biomolecular platforms and informatics investment, and co-investment from the Victorian State government and The University of Melbourne.