Shi et al. Nontechnical Summary Shi, L., S. N. Twary, H. Yoshioka, R. G. Gregerson, S. Miller, D. A. Samac, J. S. Gantt, P. T. Unkefer, ad C. P. Vance. Isolation and characterization of an asparagine synthetase gene showing enhanced expression in root nodules and dark adapted.
Mineral nutrients are critical for plant growth and reproduction.
One of the most important mineral nutrients is nitrogen, which is used to form amino acids, proteins, enzymes, and other plant components. Plants in the bean family, such as alfalfa, are able to form a symbiotic relationship with a soil bacterium that allows them to use nitrogen gas from the atmosphere, in a process called nitrogen fixation, to form amino acids. Plants lacking this ability rely on nitrogen in the form of nitrate or ammonia that is usually found in only limited amounts in soil and must be added as fertilizer for crop production. An alfalfa gene for production of the amino acid asparagine, a reaction central to nitrogen fixation, was isolated. This is the first report of the isolation of this gene from a plant.