Work

Metabolism of -aminobutyric acid during cold acclimation and freezing and its relationship to frost tolerance in barley and wheat

Year: 2006

Type: article

Abstract: Amino acid homeostasis was investigated in frost-resistant barley seedlings under either cold- or freezing-stress conditions. Total free amino acid content varied only slightly, but a substantial conversion of glutamate to gamma-aminobutyric acid (GABA) was found that was proportional to the severity of the stress. Cold acclimation caused a significant increase in amino acid pools, and induced the expression of the GABA-shunt genes. As a consequence, GABA accumulated to a higher extent during the subsequent exposure to lower temperature. A different picture was obtained with a frost-sensitive genotype, in which glutamate decarboxylation occurred during the stress as well, but the activation of the GABA shunt seemed not to take place, and free glutamate was almost depleted. Analogous results were found in frost-resistant and frost-sensitive wheat cultivars. Feeding non-hardened plants with exogenous glutamate resulted in increased GABA accumulation under low temperature. The possibility that glutamate decarboxylation and GABA metabolism would play a role in frost tolerance is discussed.

Source: Journal of Experimental Botany

DOI: 10.1093/jxb/erl141

Authors: E. Mazzucotelli, A. Tartari, L. Cattivelli, G. Forlani

Institutions: University of Ferrara, Cereal Research Centre

Language: English

Topic: Plant Stress Responses and Tolerance

Subfield: Plant Science

Field: Agricultural and Biological Sciences

Domain: Life Sciences

SDG: Zero hunger

Open Access status: bronze

Funders: Magyar Tudományos Akadémia, Università degli Studi di Ferrara