Contribution of Gamma amino butyric acid (GABA) to salt stress responses of Nicotiana sylvestris CMSII mutant and wild type plants
Küçük Resim Yok
Tarih
2012
Dergi Başlığı
Dergi ISSN
Cilt Başlığı
Yayıncı
Elsevier Gmbh
Erişim Hakkı
info:eu-repo/semantics/closedAccess
Özet
Plants accumulate high levels of Gamma amino butyric acid (GABA) in response to different environmental stresses and GABA metabolism has different functions such as osmotic and pH regulation, bypass of tricarboxylic acid cycle, and C:N balance. The cytoplasmic male sterile (CMS) II mutant of Nicotiana sylvestris has a deletion in the mitochondrial gene nad7 which encodes the NAD7 subunit of complex I which causes increased leaf respiration, impaired photosynthesis, slower growth and increased amino acid levels. In this study we aimed to elucidate the role of GABA and GABA metabolism in different genotypes of the same plant system under salt stress (100 mM NaCl) in short (24h) and long (7, 14 and 21 days) terms. We have investigated the differences in leaf fresh and dry weights, relative water content, photosynthetic efficiency (F-v/F-m), glutamate dehydrogenase (GDH. EC 1.4.1.4) and glutamate decarboxylase (GAD, EC 4.1.1.15) enzyme activities, GABA content and GAD gene expression profiles. GDH activity showed variations in CMSII and wild type (WT) plants in the first 24 h. GAD gene expression profiles were in good agreement with the GAD enzyme activity levels in CMSII and WT plants after 24 h. In long-term salinity, GAD activities increased in \NT but, decreased in CMSII. GABA accumulation in WT and CMSII plants in short and long term was induced by salt stress. Variations in GDH and GAD activities in relation to GABA levels were discussed and GABA metabolism has been proposed to be involved in better performance of CMSII plants under long term salinity. (C) 2011 Elsevier GmbH. All rights reserved.
Açıklama
Anahtar Kelimeler
GAM, GABA shunt, Salt stress, Tobacco
Kaynak
Journal of Plant Physiology
WoS Q Değeri
Q1
Scopus Q Değeri
Q1
Cilt
169
Sayı
5
