Theoretical and Applied Genetics

, Volume 113, Issue 6, pp 965–976

A branched-chain amino acid aminotransferase gene isolated from Hordeum vulgare is differentially regulated by drought stress

  • M. Malatrasi
  • M. Corradi
  • J. T. Svensson
  • T. J. Close
  • M. Gulli
  • N. Marmiroli
Original Paper

DOI: 10.1007/s00122-006-0339-6

Cite this article as:
Malatrasi, M., Corradi, M., Svensson, J.T. et al. Theor Appl Genet (2006) 113: 965. doi:10.1007/s00122-006-0339-6

Abstract

Differential display was used to isolate cDNA clones showing differential expression in response to ABA, drought and cold in barley seedling shoots. One drought-regulated cDNA clone (DD12) was further analyzed and found to encode a branched-chain amino acid aminotransferase (HvBCAT-1). A genomic clone was isolated by probing the Morex BAC library with the cDNA clone DD12 and the structure of Hvbcat-1 was elucidated. The coding region is interrupted by six introns and contains a predicted mitochondrial transit peptide. Hvbcat1 was mapped to chromosome 4H. A comparison was made to rice and Arabidopsis genes to identify conserved structural patterns. Complementation of a yeast (Saccharomyces cerevisiae) double knockout strain revealed that HvBCAT-1 can function as the mitochondrial (catabolic) BCATs in vivo. Transcript levels of Hvbcat-1, increased in response to drought stress. As the first enzyme in the branched-chain amino acid (BCAA) catabolic pathway, HvBCAT-1 might have a role in the degradation of BCAA. Degradation of BCAA could serve as a detoxification mechanism that maintains the pool of free branched-chain amino acids at low and non toxic levels, under drought stress conditions.

Copyright information

© Springer-Verlag 2006

Authors and Affiliations

  • M. Malatrasi
    • 1
    • 2
  • M. Corradi
    • 1
  • J. T. Svensson
    • 2
  • T. J. Close
    • 2
  • M. Gulli
    • 1
  • N. Marmiroli
    • 1
  1. 1.Dipartimento di Scienze Ambientali, Sez. Genetica e Biotecnologie AmbientaliUniversità di ParmaParmaItaly
  2. 2.Department of Botany and Plant SciencesUniversity of CaliforniaRiversideUSA