Expression Analysis of Aldo-Keto Reductase 1 (<i>AKR1</i>) in Foxtail Millet (<i>Setaria italica</i> L.) Subjected to Abiotic Stresses

Abstract

Foxtail millet (Setaria italica L.) is a drought-tolerant millet crop of arid and semi-arid regions. Aldo-keto reductases (AKRs) are significant part of plant defence mechanism, having an ability to confer multiple stress tolerance. In this study, AKR1 gene expression was studied in roots and leaves of foxtail millet subjected to different regimes of PEG-and NaCl-stress for seven days. The quantitative Real-time PCR expression analysis in both root and leaves showed upregulation of AKR1 gene during PEG and salt stress. A close correlation exits between expression of AKR1 gene and the rate of lipid peroxidation along with the retardation of growth. Tissue-specific differences were found in the AKR1 gene expression to the stress intensities studied. The reduction in root and shoot growth under both stress conditions were dependent on stress severity. The level of lipid peroxidation as indicated by MDA formation was significantly increased in roots and leaves along with increased stress levels. Finally, these findings support the early responsive nature of AKR1 gene and seem to be associated at least in part with its ability to contribute in antioxidant defence related pathways which could provide a better protection against oxidative stress under stress conditions.

Adaptation of Foxtail Millet (Setaria italica L.) to Abiotic Stresses: A Special Perspective of Responses to Nitrogen and Phosphate Limitations

“…OsAKR1 overexpression in tobacco lowers levels of MDA and methylglyoxal (MG) in leaf tissues under chemical and heat stress treatments (Turoczy et al, 2011). Foxtail millet AKR1 is a promising stress-responsive gene that modulates and enhances stress tolerance in major crops (Kirankumar et al, 2016). Thus, investigation of the functions of AKR in reactive carbonyl detoxification and the promotion of abiotic stress tolerance in foxtail millet is of interest.…”

Pyramiding of transcription factor, PgHSF4, and stress-responsive genes of p68, Pg47, and PsAKR1 impart multiple abiotic stress tolerance in rice (Oryza sativa L.)

“…The survival of seedlings against oxidative stress depends on the equilibrium between the generation and detoxification of ROS by a series of enzymatic and nonenzymatic mechanisms ( Hendadura et al., 2017 ; Nareshkumar et al., 2020 ). According to earlier studies, the multi-transgenes used in our study might increase the transcript level of downstream genes, which are involved in switching on the ROS scavenging system under abiotic stress conditions ( Kirankumar et al., 2016 ). Meng et al.…”

“…The marker-free gene containing the construct, PsAKR1 is possibly involved in nullifying the effect of accelerating aging. This PsAKR1 gene belongs to the Aldo ketoreductase ( AKR ) gene family, which is involved in the detoxification of the reactive carbonyl compounds generated under abiotic stresses ( Kirankumar et al., 2016 ; Nisarga et al., 2017 ; Nareshkumar et al., 2020 ). Over-expression of the PsAKR1 gene in rice and tobacco seedlings showed improved seedling vigor and viability upon accelerating aging ( Nisarga et al., 2017 ).…”