TY - JOUR
T1 - GABA mediated reduction of arsenite toxicity in rice seedling through modulation of fatty acids, stress responsive amino acids and polyamines biosynthesis
AU - Kumar, Navin
AU - Gautam, Ambedkar
AU - Dubey, Arvind Kumar
AU - Ranjan, Ruma
AU - Pandey, Ashutosh
AU - Kumari, Babita
AU - Singh, Gayatri
AU - Mandotra, Sachin
AU - Chauhan, Puneet Singh
AU - Srikrishna, Saripella
AU - Dutta, Venkatesh
AU - Mallick, Shekhar
N1 - Publisher Copyright:
© 2019 Elsevier Inc.
PY - 2019/5/30
Y1 - 2019/5/30
N2 - γ-aminobutyric acid (GABA) is a free amino acid, which helps to counteract biotic and abiotic stresses in plants. In the present study, two concentrations of GABA, i.e., 0.5 mM and 1 mM were applied to examine the tolerance of rice seedlings against As(III) (25 µM) toxicity, through the modulations of fatty acids (FAs), stress responsive amino acids (AAs) and polyamines (PAs) biosynthesis. Exogenous GABA (0.5 mM) application significantly reduced the H 2 O 2 and TBARS levels and recovered the growth parameters against As(III) stressed rice seedlings. Simultaneously, co-application of GABA (0.5 and 1 mM) and As(III), consistently enhanced the level of unsaturated fatty acids (USFA) (cis-10-pentadecanoic acid, oleic acid, α-linolenic acid and γ-linolenic acid), which was higher than saturated fatty acid (SFA). Among the USFAs, level of linolenic acid was found to be always higher with GABA application. Similarly, elevated level of AAs (proline, methionine, glutamic acid and cysteine) was also observed with the application of GABA (0.5 and 1 mM) in As(III) stressed seedlings. GABA also enhanced the expression of genes involved in the polyamine synthesis pathway namely arginine decarboxylase (AD), spermine (SPM) and spermidine (SPD) synthase against As(III) treatments, which was higher in roots than in shoots, resulting in enhanced root PAs level. Contrarily, the expression of S-adenosylmethionine decarboxylase (S-AMD) was significantly higher in shoots. Among all the PAs, level of putrescine (PUT) was found to be highest with GABA application. Overall, the study demonstrates that GABA (0.5 mM) at lower concentration plays a vital role in As(III) tolerance by enhancing the biosynthesis of USFA, AA and PA, reducing the level of TBARS and H 2 O 2 in rice seedlings.
AB - γ-aminobutyric acid (GABA) is a free amino acid, which helps to counteract biotic and abiotic stresses in plants. In the present study, two concentrations of GABA, i.e., 0.5 mM and 1 mM were applied to examine the tolerance of rice seedlings against As(III) (25 µM) toxicity, through the modulations of fatty acids (FAs), stress responsive amino acids (AAs) and polyamines (PAs) biosynthesis. Exogenous GABA (0.5 mM) application significantly reduced the H 2 O 2 and TBARS levels and recovered the growth parameters against As(III) stressed rice seedlings. Simultaneously, co-application of GABA (0.5 and 1 mM) and As(III), consistently enhanced the level of unsaturated fatty acids (USFA) (cis-10-pentadecanoic acid, oleic acid, α-linolenic acid and γ-linolenic acid), which was higher than saturated fatty acid (SFA). Among the USFAs, level of linolenic acid was found to be always higher with GABA application. Similarly, elevated level of AAs (proline, methionine, glutamic acid and cysteine) was also observed with the application of GABA (0.5 and 1 mM) in As(III) stressed seedlings. GABA also enhanced the expression of genes involved in the polyamine synthesis pathway namely arginine decarboxylase (AD), spermine (SPM) and spermidine (SPD) synthase against As(III) treatments, which was higher in roots than in shoots, resulting in enhanced root PAs level. Contrarily, the expression of S-adenosylmethionine decarboxylase (S-AMD) was significantly higher in shoots. Among all the PAs, level of putrescine (PUT) was found to be highest with GABA application. Overall, the study demonstrates that GABA (0.5 mM) at lower concentration plays a vital role in As(III) tolerance by enhancing the biosynthesis of USFA, AA and PA, reducing the level of TBARS and H 2 O 2 in rice seedlings.
KW - Amino acid
KW - Arsenic
KW - Fatty acid
KW - GABA
KW - Oryza sativa
KW - Polyamines
UR - http://www.scopus.com/inward/record.url?scp=85061212086&partnerID=8YFLogxK
U2 - 10.1016/j.ecoenv.2019.02.017
DO - 10.1016/j.ecoenv.2019.02.017
M3 - Article
C2 - 30743076
AN - SCOPUS:85061212086
SN - 0147-6513
VL - 173
SP - 15
EP - 27
JO - Ecotoxicology and Environmental Safety
JF - Ecotoxicology and Environmental Safety
ER -