Comparative RNA-Seq analysis of Betula platyphylla under low and high temperature stresses

Abstract

Background: Betula platyphylla Sukaczev is one of important tree species due to its ecological and economic value. It is a cold-tolerant tree species which also faces heat stress during summer. In the current study, RNA-Seq profiling of two-month-old B. platyphylla seedlings were conducted utilizing the MGISEQ-2000 platform.
Results: In total, 856,347,961 clean reads were obtained from 26 RNA-Seq libraries. Totally, 822,552,820 reads were successfully mapped to B. platyphylla reference genome. Further, a total of 360 and 264 DEGs were discovered under cold and heat exposure, respectively, while a total of 104 DEGs were identified under both cold and heat exposure. It was found that several pathways
including response to cold, response to heat, response to temperature stimulus, response to stress, lipid metabolic, jamonic acid and ethylene, even developmental processes were significantly enriched in GO enrichment analysis of cold and heat stress in biological process term. Several transcription factors (TFs), including MYB66, CBF2, bHLH96and bZIP7 take a pivotal role in response to temperature stresses. Furthermore, heat shock proteins were identified under cold and heat stress, respectively, suggesting these genes participate in reducing cold and heat stress detrimental effect by interacting with TFs or other genes related to abiotic stresses, chlorophyll and photosynthesis, osmoprotectants, and phytohormone as well.
Conclusion: This study not only underlying B. platyphylla’s molecular mechanism in response to temperature stresses but also provides candidate genes involved in response to temperature stresses.