Comparative Metabolomic and Transcriptomic Studies Reveal Key Metabolism Pathways Contributing to Freezing Tolerance Under Cold Stress in Kiwifruit

Abstract

Cold stress poses a serious treat to cultivated kiwifruit since this plant generally has a weak ability to tolerate freezing tolerance temperatures. Surprisingly, however, the underlying mechanism of kiwifruit’s freezing tolerance remains largely unexplored and unknown, especially regarding the key pathways involved in conferring this key tolerance trait. Here, we studied the metabolome and transcriptome profiles of the freezing-tolerant genotype KL (Actinidia arguta) and freezing-sensitive genotype RB (A. arguta), to identify the main pathways and important metabolites related to their freezing tolerance. A total of 565 metabolites were detected by a wide-targeting metabolomics method. Under (−25°C) cold stress, KEGG (Kyoto Encyclopedia of Genes and Genomes) pathway annotations showed that the flavonoid metabolic pathways were specifically upregulated in KL, which increased its ability to scavenge for reactive oxygen species (ROS). The transcriptome changes identified in KL were accompanied by the specific upregulation of a codeinone reductase gene, a chalcone isomerase gene, and an anthocyanin 5-aromatic acyltransferase gene. Nucleotides metabolism and phenolic acids metabolism pathways were specifically upregulated in RB, which indicated that RB had a higher energy metabolism and weaker dormancy ability. Since the LPCs (LysoPC), LPEs (LysoPE) and free fatty acids were accumulated simultaneously in both genotypes, these could serve as biomarkers of cold-induced frost damages. These key metabolism components evidently participated in the regulation of freezing tolerance of both kiwifruit genotypes. In conclusion, the results of this study demonstrated the inherent differences in the composition and activity of metabolites between KL and RB under cold stress conditions.

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

“…With the frequent occurrence of extreme weather, climate has become a major factor affecting the high yield of crops. Multiple responses to cold stress in plants have been shown to reflect changes in transcription and metabolism ( Zhao D. Q. et al, 2019 ; Raza et al, 2021 ; Sun et al, 2021 ). In this study, we identified 10,931 DEGs and 657 DEMs in positive ion mode and 390 DEMs in negative ion mode by multi-omics analysis.…”

“…In Nicotiana tabacum , differences exist in energy metabolism and hormone metabolism between cold-resistant and cold-sensitive cultivars ( Jin et al, 2017 ). A study on kiwifruit showed that the codeinone reductase and chalcone isomerase genes, nucleotide metabolism, and phenolic acid metabolism pathways participate in the regulation of freezing tolerance ( Sun et al, 2021 ). Furthermore, Zhao Y. et al (2019) demonstrated that differentially expressed genes (DEGs) and differentially expressed metabolites (DEMs) in wheat were significantly enriched in abscisic acid/jasmonate (ABA/JA) signaling and proline biosynthesis under cold stress.…”

Transcriptome and Metabolome Analysis Revealed the Freezing Resistance Mechanism in 60-Year-Old Overwintering Camellia sinensis

“…When plants are subjected to freezing stress, photosynthesis will be inhibited and cell structure destroyed, resulting in oxidative damage, metabolic disorder, cell damage, and other phenomena [9][10][11]. Simultaneously, plants will express a large number of resistance genes and metabolites when subjected to freezing stress [12].…”

Metabolic profiling and gene expression analyses provide insights into cold adaptation of an Antarctic moss Pohlia nutans

“…Metabolomics is currently being utilized to qualitatively and quantitatively evaluate all metabolites to offer an advanced assessment technique of the cellular state. The HPLC-MS/MS-based metabolomics are widely used to profile metabolites involved in the physiological responses to environmental challenges in plants ( Liu et al, 2021 ; Sun et al, 2021 ; Xiong et al, 2022 ). In the present study, we utilized a widely targeted metabolomics approach using the UPLC-MS/MS analytical platform to analyze the metabolite changes of P. nutans under cold stress ( Figure 2 ).…”