title: Nitrogen-regulated changes in total amino acid profile of maize genotypes having contrasting response to nitrogen deficit.
abstract: Sustainable development of cellular organisms depends on a precise coordination between the carbon and nitrogen metabolisms within the living system. Inorganic N is assimilated into amino acids which serve as an important N source for various regulatory metabolic pathways in plants. This study investigates the role of amino acids in C/N balance by examining changes in amino acid profile in the leaves and roots of low-N-tolerant (PHEM-2) and low-N-sensitive (HM-4) maize genotypes grown hydroponically under N-sufficient (4.5 mM), N-deficient (0.05 mM) and N-restoration conditions. N application effectively altered the level of cysteine, methionine, asparagine, arginine, phenylalanine, glycine, glutamine, aspartate and glutamate in both genotypes. Under low N (0.05 mM), the asparagine and glutamine contents increased, while those of glutamate, phenylalanine and aspartate decreased in both genotypes. However, serine content increased in PHEM-2 but decreased in HM-4. Resupply of N to low-N-grown plants of both genotypes restored the amino acids level to that in the control; the restoration was quicker and more consistent in PHEM-2 than in HM-4. Based on alteration of amino acid level, a strategy can be developed to improve the ability of maize to adapt to low-N environments by way of an improved N utilization.
authors.affiliation: Molecular Ecology Laboratory, Department of Botany, Faculty of Science, Hamdard University, New Delhi, 110062, India.
authors.forename: Arshid Hussain
authors.initials: AH
authors.lastname: Ganie
authors.affiliation: Department of Botany, Aligarh Muslim University, Aligarh, 202002, India.
authors.forename: Altaf
authors.initials: A
authors.lastname: Ahmad
authors.affiliation: Molecular Ecology Laboratory, Department of Botany, Faculty of Science, Hamdard University, New Delhi, 110062, India.
authors.forename: Peerzada Yasir
authors.initials: PY
authors.lastname: Yousuf
authors.affiliation: Division of Plant Physiology, ICAR-Indian Agricultural Research Institute, New Delhi, 110012, India.
authors.forename: Renu
authors.initials: R
authors.lastname: Pandey
authors.affiliation: Department of Pharmacognosy & Pharmaceutical Chemistry, Faculty of Pharmacy, Jamia Hamdard, New Delhi, 110062, India.
authors.forename: Sayeed
authors.initials: S
authors.lastname: Ahmad
authors.affiliation: Department of Plant Production, College of Food and Agricultural Sciences, King Saud University, Post Box 2460, Riyadh, 11451, Saudi Arabia.
authors.forename: Ibrahim M
authors.initials: IM
authors.lastname: Aref
authors.affiliation: Molecular Ecology Laboratory, Department of Botany, Faculty of Science, Hamdard University, New Delhi, 110062, India. iqbalg5@yahoo.co.in.
authors.forename: Muhammad
authors.initials: M
authors.lastname: Iqbal
mesh_terms: D000596:Amino Acids / Q000378:metabolism*; D018506:Gene Expression Regulation, Plant; D005838:Genotype; D009584:Nitrogen / Q000378:metabolism*; D018515:Plant Leaves / Q000254:growth & development / Q000378:metabolism; D018517:Plant Roots / Q000254:growth & development / Q000378:metabolism; D013312:Stress, Physiological; D003313:Zea mays / Q000254:growth & development / Q000378:metabolism*
chemical_list: D000596:Amino Acids; D009584:Nitrogen
keywords: Amino acids; HPLC; Maize genotypes; Nitrogen; Nitrogen use efficiency