Integrated Transcriptomics and Metabolomics Analysis Reveal Key Metabolism Pathways Contributing to Cold Tolerance in Peanut

Abstract

Low temperature (non-freezing) is one of the major limiting factors in peanut (Arachis hypogaea L.) growth, yield, and geographic distribution. Due to the complexity of cold-resistance trait in peanut, the molecular mechanism of cold tolerance and related gene networks were largely unknown. In this study, metabolomic analysis of two peanut cultivars subjected to chilling stress obtained a set of cold-responsive metabolites, including several carbohydrates and polyamines. These substances showed a higher accumulation pattern in cold-tolerant variety SLH than cold-susceptible variety ZH12 under cold stress, indicating their importance in protecting peanut from chilling injuries. In addition, 3,620 cold tolerance genes (CTGs) were identified by transcriptome sequencing, and the CTGs were most significantly enriched in the “phenylpropanoid biosynthesis” pathway. Two vital modules and several novel hub genes were obtained by weighted gene co-expression network analysis (WGCNA). Several key genes involved in soluble sugar, polyamine, and G-lignin biosynthetic pathways were substantially higher and/or responded more quickly in SLH (cold tolerant) than ZH12 (cold susceptible) under low temperature, suggesting they might be crucial contributors during the adaptation of peanut to low temperature. These findings will not only provide valuable resources for study of cold resistance in peanut but also lay a foundation for genetic modification of cold regulators to enhance stress tolerance in crops.

Transcriptome and Metabolome Analyses Reveal Molecular Responses of Two Pepper (Capsicum annuum L.) Cultivars to Cold Stress

“…Put, Spd, and Spm are major components in plants and play vital roles in plant growth, development, and stress response ( Pál et al, 2015 ; Ghosh et al, 2021 ; Gonzalez et al, 2021 ). The levels of PAs increase considerably in response to cold stress ( Amini et al, 2021 ; Jiao et al, 2021 ; Wang et al, 2021 ), and a cold-tolerant rice cultivar showed a greater accumulation of PAs than the sensitive cultivars ( Sheteiwy et al, 2017 ). This study showed that the content of PAs increased in both genotypes under cold stress but the increase in GZ was higher than that in XS, suggesting that the changes in Put, Spd, and Spm levels play a key role in response to cold stress ( Supplementary Figure 6 ).…”

Transcription-associated metabolomic profiling reveals the critical role of frost tolerance in wheat

“…Recent studies have shown that the expression of structural genes， such as Chalcone synthase ( CHS ) and chalcone isomerase ( CHI )，were induced by cold stress in phenylpropanoid pathway. Therefore, the accumulation of flavonoids and lignin can adapt plants to low-temperature environment [ 80 ]. This study found that some frost-response genes involved in the phenylpropanoid metabolism biosynthesis were expressed higher after low-temperature treatment than before.…”

Low Temperature Stress Tolerance: An Insight Into the Omics Approaches for Legume Crops

“…Additionally, a decrease in cold tolerance in Arabidopsis mutant air12 was detected, which was recovered by overexpression of MfAIR12. In comparison to wild type, MfAIR12 transgenic lines had elevated levels of ascorbate redox state, and ascorbic acid and transcripts of the CBF transcription factors and their downstream cold-responsive genes, but decreased levels in air12 mutant lines (Wang et al, 2021). Also, MfERF1, a cold-responsive ERF, was identified from Medicago falcata, with exceptional cold tolerance.…”

“…A group of cold-responsive metabolites was discovered during the metabolomic study of two peanut cultivars exposed to chilling stress, including various sugars and polyamines. Under cold stress, these compounds accumulated more in the cold-resistant variety (SLH) than in the cold-susceptible variety (ZH12), demonstrating their role in protecting peanuts against chilling damage (Wang et al, 2021). Cold-tolerant plants exhibit greater growth amplitude of these osmotic regulatory molecules than cold-sensitive plants due to their increased levels of proline, soluble carbohydrates, and soluble proteins in the cytosol.…”