Comparative Transcriptomics and Proteomics Analyses of Leaves Reveals a Freezing Stress-Responsive Molecular Network in Winter Rapeseed (Brassica rapa L.)

Abstract

Winter rapeseed is susceptible to low temperature during winter in Northwest China, which could lead to a severe reduction of crop production. The freezing temperature could stress the whole plant, especially the leaf, and ultimately harm the survival rate of winter rapeseed. However, the molecular mechanism underlying freezing tolerance is still unclear in winter rapeseed. In this study, a comprehensive investigation of winter rapeseed freezing tolerance was conducted at the levels of transcript, protein, and physiology and biochemistry, using a pair of freezing-sensitive and freezing-resistant cultivars NQF24 and 17NTS57. There were 4,319 unique differentially expressed genes (DEGs) and 137 unique differentially abundant proteins (DAPs) between two cultivars identified in leaf under freezing stress. Function enrichment analysis showed that most of the enriched DEGs and DAPs were involved in plant hormone signal transduction, alpha-linolenic/linoleic acid metabolism, peroxisome, glutathione metabolism, fatty acid degradation, and secondary metabolite biosynthesis pathways. Based on our findings, it was speculated that freezing tolerance formation is caused by increased signal transduction, enhanced biosynthesis of protein, secondary metabolites, and plant hormones, elevated energy supply, greater reactive oxygen species scavenging, and lower lipid peroxidation as well as stronger cell stability in leaf under freezing stress. These results provide a comprehensive profile of leaf response under freezing stress, which have potential to be used as selection indicators of breeding programs to improve freezing tolerance in rapeseed.

DNA methylation affects freezing tolerance in winter rapeseed by mediating the expression of genes related to JA and CK pathways

“…In addition, it has become increasingly evident that ROS scavenging enzymes are indispensable to maintain normal cellular redox homeostasis (Ray et al, 2012). In our previous study, ROS scavenging enzyme activities were obviously increased in NS plants under freezing stress (Wei et al, 2021a). These results are in agreement with findings reported by Zeng et al (2018).…”

“…Plant samples, freezing stress treatments and overwintering rate assessment One freezing-resistant winter rapeseed cultivar NTS57 (NS, with a more than 85% overwinter survival rate at −26 °C), widely planted in Northwest China and used in this study, was provided by Gansu Agricultural University (Wei et al, 2021a). Seedlings of the cultivar NTS57 were grown in plastic pots (5 L) filled with soil from 2015 to 2017.…”

“…The expressions of nine candidate freezing-responsive genes were analyzed by qRT-PCR. The qRT-PCR was performed according to protocol of Wei et al (2021a) . All primers were listed in Supplementary Table S1 .…”

“…Freezing stress (<0 °C), one of the major abiotic stresses, threatens crop yield as well as quality and causes tremendous agricultural yield penalty and economic losses worldwide (Ding et al, 2020). Moreover, freezing stress can result in membrane lipid peroxidation and cellular structural damage and reduce the activities of reactive oxygen species (ROS)-scavenging enzymes during seedling development (Wei et al, 2021a). Hence, adaptation to different environments, especially to extremely low temperature conditions, plays a pivotal role in the widespread geographical distribution for crops.…”

Increase Crop Resilience to Heat Stress Using Omic Strategies

“…Integrated analysis of transcriptomics and proteomics was applied to various crops, such as soybean ( Valdés-López et al, 2016 ), rice ( Wang et al, 2017 ; Anupama et al, 2019 ), maize ( Zhang et al, 2019 ), barley ( Lai et al, 2020 ), and rapeseed ( Mehmood et al, 2021 ; Wei et al, 2021 ). Valdés-López et al (2016) found 10 gene regulatory key modules and a variety of proteins that played roles in the heat tolerance of soybean at high temperatures ( Valdés-López et al, 2016 ).…”