Zinc Deficiency Up-Regulates Expression of High-Affinity Phosphate Transporter Genes in Both Phosphate-Sufficient and -Deficient Barley Roots

• Published in: Plant physiology (Bethesda) Vol. 124; no. 1; pp. 415 - 422
• Main Authors: Chunyuan Huang, Susan Jane Barker, Langridge, Peter, Smith, Frank W., Robin David Graham
• Format: Journal Article
• Language: English
• Published: Rockville, MD American Society of Plant Physiologists 01.09.2000
• Subjects: Absorption. Translocation of ions and substances. Permeability; Acid soils; Agricultural soils; Agronomy. Soil science and plant productions; Barley; Biological and medical sciences; Carrier Proteins - genetics; Carrier Proteins - metabolism; Chelating Agents - pharmacology; Crop harvesting; Economic plant physiology; Edetic Acid - analogs & derivatives; Edetic Acid - pharmacology; Environmental Stress and Adaptation; Fundamental and applied biological sciences. Psychology; Gene Expression Regulation, Plant; Genes; Hordeum - genetics; Hordeum - growth & development; Hordeum - physiology; Manganese - metabolism; Manganese - pharmacology; Membrane Proteins - genetics; Membrane Proteins - metabolism; Nutrient solutions; Nutrition. Photosynthesis. Respiration. Metabolism; Phosphate-Binding Proteins; Phosphates; Phosphates - metabolism; Phosphorus - pharmacology; Plant growth; Plant physiology and development; Plant roots; Plant Roots - genetics; Plant Roots - growth & development; Plant Roots - physiology; Plants; Signal Transduction; Soil; Up-Regulation; Water and solutes. Absorption, translocation and permeability; Zinc - metabolism; Monocotyledones; Hordeum vulgare; Nutrition; Root; Deficiency; Phosphorus; Gene expression; Inorganic element; Cereal crop; Zinc; Signal transduction; Regulation(control); Absorption; Gramineae; Angiospermae; Plasma membrane; Nutrient; Spermatophyta; Biological accumulation; Carrier protein
• ISSN: 0032-0889; 1532-2548
• DOI: 10.1104/pp.124.1.415

Phosphate (P) is taken up by plants through high-affinity P transporter proteins embedded in the plasma membrane of certain cell types in plant roots. Expression of the genes that encode these transporters responds to the P status of the plants, and their transcription is normally tightly controlled. However, this tight control of P uptake is lost under Zn deficiency, leading to very high accumulation of P in plants. We examined the effect of plant Zn status on the expression of the genes encoding the HVPT1 and HVPT2 high-affinity P transporters in barley (Hordeum vulgare L. cv Weeah) roots. The results show that the expression of these genes is intimately linked to the Zn status of the plants. Zn deficiency induced the expression of genes encoding these P transporters in plants grown in either P-sufficient or -deficient conditions. Moreover, the role of Zn in the regulation of these genes is specific in that it cannot be replaced by manganese (a divalent cation similar to Zn). It appears that Zn plays a specific role in the signal transduction pathway responsible for the regulation of genes encoding high-affinity P transporters in plant roots. The significance of Zn involvement in the regulation of genes involved in P uptake is discussed.