Phytochelatins Are Involved in Differential Arsenate Tolerance in Holcus lanatus1

AUTOR(ES)

Hartley-Whitaker, Jeanette

FONTE

American Society of Plant Physiologists

RESUMO

Arsenate tolerance is conferred by suppression of the high-affinity phosphate/arsenate uptake system, which greatly reduces arsenate influx in a number of higher plant species. Despite this suppressed uptake, arsenate-tolerant plants can still accumulate high levels of As over their lifetime, suggesting that constitutive detoxification mechanisms may be required. Phytochelatins are thiol-rich peptides, whose production is induced by a range of metals and metalloids including arsenate. This study provides evidence for the role of phytochelatins in the detoxification of arsenate in arsenate-tolerant Holcus lanatus. Elevated levels of phytochelatin were measured in plants with a range of tolerance to arsenate at equivalent levels of arsenate stress, measured as inhibition of root growth. The results suggest that arsenate tolerance in H. lanatus requires both adaptive suppression of the high-affinity phosphate uptake system and constitutive phytochelatin production.

Documentos Relacionados

• The Distribution of Arsenate and Arsenite in Shoots and Roots of Holcus lanatus is Influenced by Arsenic Tolerance and Arsenate and Phosphate Supply
• The Nature of Arsenic-Phytochelatin Complexes in Holcus lanatus and Pteris cretica1
• Reactive Oxygen Species Are Involved in Brassinosteroid-Induced Stress Tolerance in Cucumber1[W]
• Homo-Phytochelatins Are Synthesized in Response to Cadmium in Azuki Beans1
• Azuki Bean Cells Are Hypersensitive to Cadmium and Do Not Synthesize Phytochelatins1