Open AccessEffect of chilling and acclimation on the activity of glutamine synthetase isoforms in maize seedlings
Author(s) -
Ana Simonović,
Marc H. Anderson
Publication year - 2007
Publication title -
archives of biological sciences
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.217
H-Index - 25
eISSN - 1821-4339
pISSN - 0354-4664
DOI - 10.2298/abs0703177s
Subject(s) - coleoptile , glutamine synthetase , acclimatization , etiolation , biology , enzyme assay , biochemistry , cytosol , gene isoform , glutamine , enzyme , botany , gene , amino acid
Effects of chilling and acclimation on the activity of cytosolic (GS1) and plastidic (GS2) isoforms of glutamine synthetase (E.C. 6.3.1.2) were studied in chilling-sensitive and acclimation-responsive maize inbred G50. Glutamine synthetase activity in mesocotyls and roots of chilled (7 d/4ºC) and rewarmed (1 d/27ºC) etiolated plants was "1/3 that of controls. In coleoptiles+leaves of light-grown plants, GS1 was reduced to 75%, and GS2 to 50%. Acclimation (3 d/14ºC) increased GS activity and alleviated the effects of chilling. Exposure to H2O2 or menadione also reduced GS activity. Since chilling causes oxidative stress in maize, acclimation probably preserves GS activity by protecting GS from oxidative inactivation.