Adaptation and response of Kobresia littledalei to cold stress conditions

Kobresia plant ( Kobresia littledalei ) is the dominant vegetation type in the Qinghai-Tibet Plateau region where the temperatures can be extremely low and harsh during winter. However, the potential molecular mechanisms that respond to cold remain to be fully elucidated. In this study, we applied the use of high-throughput sequencing technology in investigating the genes involved in Kobresia plant acclimation and response to cold stress. Kobresia plants were grown in pots for 7 days in a 25 °C greenhouse and thereafter subdivided into 6 batches (Kli-0 to Kli-5) that were exposed to cold-treatment in a – 5 °C cryogenic treatment room at varying timelines (0–48 h); With Kli-0 batch being the control (untreated). We sequenced the treated samples and obtained 90,331,944 clean reads. Clustering analysis assigned a total of 214,531 assembled trinity genes. For functional annotation, all the assembled unigenes were aligned against public databases that include NCBI’s Pfam (Pfam protein families), Uniprot (Swiss-Prot), KEGG (Kyoto Encyclopedia of Genes and Genomes database) and KOG (eukaryotic orthologous groups) classification system was used to assign the possible functions of the obtained unigenes. From these, we linked a great number of candidate genes to the cold stress response. Several significant DEGs and metabolic responses were identified and discussed. Further, we identified significant DEG’s from the transcriptome data. AP2/ERF-ERF gene family could be playing a significant role that enhances the survival of K. littledalei to cold stress conditions. In conclusion, our findings herein further the general understanding of Kobresia plants' adaptation and responses to cold stress through the molecular mechanisms involved in signal regulation and cold resistance.