Dr Mamoru Okamoto
My research interest is all about nitrogen from simple molecule such as nitric oxide (NO) to more complex molecules including amino acids and proteins. Nitrogen (N) is an essential nutrient for plant growth and development. Therefore, N fertilisers are one of the highest input costs for crop productions. However, N use efficiency of crop plants are relatively low and excess fertilisers run off and cause pollutions. One of my research questions is how can plants use nitrogen fertilisers more efficiently? To answer this question, we try to find genetic diversity for N use and identify genes responsible for better N uptake and utilization in wheat. We also conduct research on grain quality especially protein content, which is an important criteria for grain classification, and highly influenced by N status of plants. We use genetic approaches to dissect the mechanisms of grain protein accumulation, and aim to increase protein content without compromising other good traits. My other interests include N uptake from roots and shoots, N transporters, and NO synthesis and signalling in plants.
I lead the nitrogen program of the ARC Industrial Transformation Research Hub for Wheat, and an ARC Linkage project.
For more information: http://www.wheathub.com.au/
|2017||Plett, D., Holtham, L., Okamoto, M. & Garnett, T. (2017). Nitrate uptake and its regulation in relation to improving nitrogen use efficiency in cereals. Seminars in Cell and Developmental Biology, -.
|2017||Qiongyan, L., Cai, J., Berger, B., Okamoto, M. & Miklavcic, S. (2017). Detecting spikes of wheat plants using neural networks with Laws texture energy. Plant Methods, 13, 1, 83-1-83-13.
|2016||Mahjourimajd, S., Taylor, J., Sznajder, B., Timmins, A., Shahinnia, F., Rengel, Z. ... Langridge, P. (2016). Genetic basis for variation in wheat grain yield in response to varying nitrogen application. H. Nguyen (Ed.). PLoS ONE, 11, 7, 1-18.
|2016||Cai, J., Okamoto, M., Atieno, J., Sutton, T., Li, Y. & Miklavcic, S. (2016). Quantifying the onset and progression of plant senescence by color image analysis for high throughput applications. P. Kalaitzis (Ed.). PLoS ONE, 11, 6, 0157102-1-0157102-21.
|2016||Mahjourimajd, S., Kuchel, H., Langridge, P. & Okamoto, M. (2016). Evaluation of Australian wheat genotypes for response to variable nitrogen application. Plant and Soil, 399, 1, 247-255.
|2016||Mahjourimajd, S., Taylor, J., Rengel, Z., Khabaz-Saberi, H., Kuchel, H., Okamoto, M. & Langridge, P. (2016). The genetic control of grain protein content under variable nitrogen supply in an Australian wheat mapping population. H. T. Nguyen (Ed.). PLoS ONE, 11, 7, -.
|2015||Han, M., Okamoto, M., Beatty, P., Rothstein, S. & Good, A. (2015). The genetics of nitrogen use efficiency in crop plants. Annual Review of Genetics, 49, 1, 9.1-9.21.
|2015||Garnett, T., Plett, D., Heuer, S. & Okamoto, M. (2015). Genetic approaches to enhancing nitrogen-use efficiency (NUE) in cereals: challenges and future directions. Functional Plant Biology, 42, 10, 921-941.
|2014||Chiasson, D., Loughlin, P., Mazurkiewicz, D., Mohammadidehcheshmeh, M., Fedorova, E., Okamoto, M. ... Kaiser, B. (2014). Soybean SAT1 (Symbiotic Ammonium Transporter 1) encodes a bHLH transcription factor involved in nodule growth and NH₄⁺ transport. Proceedings of the National Academy of Sciences of the United States of America, 111, 13, 4814-4819.
|2012||Wang, W., Kohler, B., Cao, F., Liu, G., Gong, Y., Sheng, S. ... Liu, L. (2012). Rice DUR3 mediates high-affinity urea transport and plays an effective role in improvement of urea acquisition and utilization when expressed in Arabidopsis. New Phytologist, 193, 2, 432-444.
|2007||Tischner, R., Galli, M., Heimer, Y., Bielefeld, S., Okamoto, M., Mack, A. & Crawford, N. (2007). Interference with the citrulline-based nitric oxide synthase assay by argininosuccinate lyase activity in Arabidopsis extracts. FEBS Journal, 274, 16, 4238-4245.
|2007||Li, W., Wang, Y., Okamoto, M., Crawford, N., Siddiqi, M. & Glass, A. (2007). Dissection of the AtNRT2.1:AtNRT2.2 inducible high-affinity nitrate transporter gene cluster. Plant Physiology, 143, 1, 425-433.
|2006||Okamoto, M., Kumar, A., Li, W., Wang, Y., Siddiqi, M., Crawford, N. & Glass, A. (2006). High-affinity nitrate transport in roots of Arabidopsis depends on expression of the NAR2-like gene AtNRT3.1. Plant Physiology, 140, 3, 1036-1046.
|2005||Unkles, S., Rouch, D., Wang, Y., Siddiqi, M., Okamoto, M., Stephenson, R. ... Glass, A. (2005). Determination of the essentiality of the eight cysteine residues of the NrtA protein for high-affinity nitrate transport and the generation of a functional cysteine-less transporter. Biochemistry, 44, 14, 5471-5477.
|2003||Guo, F. Q., Okamoto, M. & Crawford, N. (2003). Identification of a plant nitric oxide synthase gene involved in hormonal signaling. Science, 302, 5642, 100-103.
|2003||Hanawa, F., Okamoto, M. & Towers, G. (2003). Inhibition of restriction enzyme's DNA sequence recognition by PUVA treatment. Nucleic Acids Research, (sup 2001), 3, 297-298.|
|2003||Kumar, A., Silim, S., Okamoto, M., Siddiqi, M. & Glass, A. (2003). Differential expression of three members of the AMT1 gene family encoding putative high-affinity NH₄⁺ transporters in roots of Oryza sativa subspecies indica. Plant Cell and Environment, 26, 6, 907-914.
|2003||Wang, R., Okamoto, M., Xing, X. & Crawford, N. (2003). Microarray analysis of the nitrate response in Arabidopsis roots and shoots reveals over 1,000 rapidly responding genes and new linkages to glucose, trehalose-6-phosphate, iron, and sulfate metabolism. Plant Physiology, 132, 2, 556-567.
|2003||Okamoto, M., Vidmar, J. & Glass, A. (2003). Regulation of NRT1 and NRT2 gene families of Arabidopsis thaliana: Responses to nitrate provision. Plant and Cell Physiology, 44, 3, 304-317.
|2002||Glass, A., Britto, D., Kaiser, B., Kinghorn, J., Kronzucker, H., Kumar, A. ... Vidmar, J. (2002). The regulation of nitrate and ammonium transport systems in plants. Journal of Experimental Botany, 53, 370, 855-864.|
|2001||Glass, A., Britto, D., Kaiser, B., Kronzucker, H., Kumar, A., Okamoto, M. ... Zhuo, D. (2001). Nitrogen transport in plants, with an emphasis on the regulation of fluxes to match plant demand. Journal of Plant Nutrition and Soil Science-Zzeitschrift fur Pflanzenernahrung und Bodenkunde, 164, 2, 199-207.
|1999||Zhuo, D., Okamoto, M., Vidmar, J. J. & Glass, A. D. (1999). Regulation of a putative high-affinity nitrate transporter (Nrt2;1At) in roots ofArabidopsis thaliana. The Plant Journal, 17, 5, 563-568.
|2017||Plett, D., Garnett, T. & Okamoto, M. (2017). Molecular genetics to discover and improve nitrogen use efficiency in crop plants. In M. Hossain, T. Kamiya, D. Burritt, L. -. S. Tran & T. Fujiwara (Eds.), Plant Macronutrient Use Efficiency: Molecular and Genomic Perspectives in Crop Plants (pp. 93-122). Cambridge: Elsevier.
|2016||Tricker, P., Haefele, S. M. & Okamoto, M. (2016). The interaction of drought and nutrient stress in wheat: Opportunities and limitations. In P. Ahmad (Ed.), Water Stress and Crop Plants: A Sustainable Approach (pp. 695-710). United Kingdom: Wiley.
|2013||Anbalagan, R., Kovalchuk, N., Parent, B., Kovalchuk, A., Okamoto, M., Whitford, R. & Haefele, S. M. (2013). A phenotyping platform for transgenic wheat: method and initial results. 20th International Congress on Modelling and Simulation (MODSIM). J. Piantadosi, R. Anderssen & J. Boland (Eds.) Adelaide, AUSTRALIA.|
- ARC Linkage Project (LP140100239) 2015-2018 Small molecules with large effect: The dual role of nitrogen-containing metabolites in stress tolerance and nutrient recycling: Lead CI
- ARC Industrial Transformation Research Hub (IH130200027) 2015-2020 Wheat in a hot and dry climate: Original CI
Current PhD students:
- Alberto Casartelli (enrolled 2014) - The purine catabolic pathway in wheat: source of nutrients and protective metabolites
- Margaret Kirika (enrolled 2016) - Physiological and molecular characterization of foliar N uptake in wheat
- Vahid Rhimi (enrolled 2016) - Understanding the interactions between biomass, yield and grain protein content in hard and soft wheat
|2010 - 2013||Australian Centre for Plant Functional Genomics||Scientific research||Australia|