Combined Transcriptome and Metabolome Profiling Provide Insights into Cold Responses in Rapeseed (Brassica napus L.) Genotypes with Contrasting Cold-Stress Sensitivity

Abstract

Low temperature is a major environmental factor, which limits rapeseed (Brassica napus L.) growth, development, and productivity. So far, the physiological and molecular mechanisms of rapeseed responses to cold stress are not fully understood. Here, we explored the transcriptome and metabolome profiles of two rapeseed genotypes with contrasting cold responses, i.e., XY15 (cold-sensitive) and GX74 (cold-tolerant). The global metabolome profiling detected 545 metabolites in siliques of both genotypes before (CK) and after cold-stress treatment (LW). The contents of several sugar metabolites were affected by cold stress with the most accumulated saccharides being 3-dehydro-L-threonic acid, D-xylonic acid, inositol, D-mannose, D-fructose, D-glucose, and L-glucose. A total of 1943 and 5239 differentially expressed genes were identified from the transcriptome sequencing in XY15CK_vs_XY15LW and GX74CK_vs_GX74LW, respectively. We observed that genes enriched in sugar metabolism and biosynthesis-related pathways, photosynthesis, reactive oxygen species scavenging, phytohormone, and MAPK signaling were highly expressed in GX74LW. In addition, several genes associated with cold-tolerance-related pathways, e.g., the CBF-COR pathway and MAPK signaling, were specifically expressed in GX74LW. Contrarily, genes in the above-mentioned pathways were mostly downregulated in XY15LW. Thus, our results indicate the involvement of these pathways in the differential cold-stress responses in XY15 and GX74.

How Antioxidants, Osmoregulation, Genes and Metabolites Regulate the Late Seeding Tolerance of Rapeseeds (Brassica napus L.) during Wintering

“…The Yangtze River Basin, as an important production area of rice and rapeseed, is experiencing the problem of rice-rape stubble contradiction, which is becoming more serious as the global environment changes [32]. With a delay in its seeding date, rapeseed becomes more susceptible to the influence of extreme weather.…”

Temperature‐smart plants: A new horizon with omics‐driven plant breeding

“…Cold‐tolerant (C18) and cold‐sensitive (C6) rapeseed genotypes subjected to CS (8/4°C day/night for 7 days) exhibited 31 metabolites related to carbohydrates, amino acids, secondary metabolites, lipids, membrane transport, cofactors and vitamins, nucleotides, and energy metabolism (Raza et al, 2021b). Another metabolic profiling study on cold‐tolerant (GX74) and sensitive (XY15) rapeseed genotypes exposed to short CS treatments (−2°C for 2 h) detected 545 metabolites primarily involved in sugar metabolism, ROS scavenging, photosynthesis, phytohormone signaling, and MAPK signaling metabolism pathways (Liu et al, 2022b). Camellia oleifera flower buds subjected to CS (6°C) exhibited differential expression of metabolites associated with carbohydrate, phenylpropanoid, and hormone metabolism in two contrasting cultivars (Wang et al, 2023).…”