Comparative transcriptome combined with metabolome analyses revealed key factors involved in nitric oxide (NO)-regulated cadmium stress adaptation in tall fescue

Abstract

Background: It has been reported that nitric oxide (NO) could ameliorate cadmium (Cd) toxicity in tall fescue; however, the underlying mechanisms of NO mediated Cd detoxification are largely unknown. In this study, we investigated the possible molecular mechanisms of Cd detoxification process by comparative transcriptomic and metabolomic approaches. Results: The application of Sodium nitroprusside (SNP) as NO donor decreased the Cd content of tall fescue by 11% under Cd stress (T1 treatment), but the Cd content was increased by 24% when treated with Carboxy-PTIO (c-PTIO) together with Nitro-L-arginine methyl ester (L-NAME) (T2 treatment). RNA-seq analysis revealed that 904 (414 up-and 490 down-regulated) and 118 (74 up-and 44 down-regulated) DEGs were identified in the T1 vs Cd (only Cd treatment) and T2 vs Cd comparisons, respectively. Moreover, metabolite profile analysis showed that 99 (65 upand 34-down-regulated) and 131 (45 up-and 86 down-regulated) metabolites were altered in the T1 vs Cd and T2 vs Cd comparisons, respectively. The integrated analyses of transcriptomic and metabolic data showed that 81 DEGs and 15 differentially expressed metabolites were involved in 20 NO-induced pathways. The dominant pathways were antioxidant activities such as glutathione metabolism, arginine and proline metabolism, secondary metabolites such as flavone and flavonol biosynthesis and phenylpropanoid biosynthesis, ABC transporters, and nitrogen metabolism. Conclusions: In general, the results revealed that there are three major mechanisms involved in NO-mediated Cd detoxification in tall fescue, including (a) antioxidant capacity enhancement; (b) accumulation of secondary metabolites related to cadmium chelation and sequestration; and (c) regulation of cadmium ion transportation, such as ABC transporter activation. In conclusion, this study provides new insights into the NO-mediated cadmium stress response.

iTRAQ-Based Proteomic Analysis Reveals the Role of the Biological Control Agent, Sinorhizobium fredii Strain Sneb183, in Enhancing Soybean Resistance Against the Soybean Cyst Nematode

“…In this study, five PAL were identified to be upregulated in Sneb183 + J2 vs. J2, these proteins provide novel insights into the understanding of the induce resistance in soybean in response to Sneb183. Trans-cinnamate 4-monooxygenase that is also called as cinnamate 4-hydroxylase (C4H) participates in the synthesis of numerous polyphenoid compounds by plants when challenged by pathogens, such as flavones, isoflavonoids, and lignin (Zhu et al, 2020). The accumulation of the enzyme in our study could be related to the accumulation of flavones and isoflavonoids, increasing lignification of the cell wall and then enhance soybean resistance, which is similar to the results in Ulmus pumila (Zuo et al, 2019).…”

The Effect of Nitric Oxide on Amaranthus Tricolor L. Under Cadmium Stress

“…(Fancy et al 2017). Mitigation of Cd toxicity and decreasing lipid peroxidation via exogenous application of SNP was also reported by other studies (Kaya et al 2019;Sharma et al 2020;Zhu et al 2020). Kaya et al (2019) reported signi cantly higher production of H 2 O 2 and MDA in wheat plants treated with Cd in comparison with the control treatment.…”

“…However, there is no report, to the best of our knowledge, regarding the effect of NO on A. tricolor under Cd toxicity. The investigation regarding the impacts of NO on heavy metal toxicity in different species, according to Zhu et al (2020), is still a research interest. Zhu et al (2020) reported that NO can reduce the damaging effects of other free radicals generated under Cd toxicity in tall fescue plants leading them to tolerant oxidative stress caused by Cd toxicity and stimulated plants to produce much mass in compare to control condition.…”

“…The investigation regarding the impacts of NO on heavy metal toxicity in different species, according to Zhu et al (2020), is still a research interest. Zhu et al (2020) reported that NO can reduce the damaging effects of other free radicals generated under Cd toxicity in tall fescue plants leading them to tolerant oxidative stress caused by Cd toxicity and stimulated plants to produce much mass in compare to control condition. Conversely, a high concentration of NO may lead to higher oxidative stress on account of its oxidant free radical form, such as what was observed in our study.…”

Unveiling Molecular Mechanisms of Nitric Oxide-Induced Low-Temperature Tolerance in Cucumber by Transcriptome Profiling

“…Moreover, it was revealed that exogenous NO increased plant LT tolerance at the physiological level, such as by improving plant photosynthesis, carbohydrate metabolism, antioxidant enzyme activity, and reactive oxygen species (ROS) metabolism [ 7 , 8 , 9 , 10 ]. In addition, NO also plays a critical role in plant stress response through mobilizing the flavonoids and other secondary metabolites, such as salicylic acid (SA), ethylene, IAA, ABA, and jasmonic acid (JA), and activating the expression of related genes encoding ABC transporter, glutathione S -transferases (GSTs) and cytochromes P450 [ 11 , 12 , 13 ].…”