Correlation Analysis of Response of Sorbus pohuashanensis Leaves to High-temperature Stress Based on Label Free-based Quantitative Proteomic and Transcriptomic

Abstract Background: High-temperature stress is the main abiotic stress of Sorbus pohuashanensis (Hance) Hedl. introduced from the mountains to plain areas. To investigate the mechanisms of heat response in S. pohuashanensis, we compared the transcriptome and proteome after high temperature stress at 43 °C for 8 h. Results: Proteomic sequencing yielded 92 (51 upregulated and 41 downregulated) DAPs, involving heat-killed proteins, molecular chaperones, energy metabolism, signal transduction, cellular autophagy, and reactive oxygen species scavenging systems. TEM results indicated that high-temperature stress led to disruption of the structural integrity of chloroplasts in mature chloroplast cells, reduction of chloroplast vesicle-like lamellae, accumulation of lipophilic granules, and an increase in the number of vesicles. Quantitative combined transcriptomic and proteomic analyses yielded 34 pairs of DAPs/DEG-associated genes. The functional enrichment of these DAPs/DEGs indicated that their functions were related to chaperones, energy metabolism, ROS scavenging system, and cell wall modification. Conclusion: 92 DAPs were identified in the proteomic analysis of S. pohuashanensis under high temperature stress, and co-regulatory analysis revealed 34 DAPs/DEGs in the comparison group, with 24 genes having the same protein and mRNA expression trends and 10 genes with opposite protein and mRNA expression trends. These genes are collectively involved in response to high temperature stress by encoding proteins related to molecular chaperones, energy metabolism, ROS scavenging systems and cell wall modifications. These results provide a basis for the complex HSF–Hsp regulatory network contributes to the heat tolerance of S. pohuashanensis.