Expression of Heat Shock Proteins by Heat Stress in Soybean

Heat stress is one of the factors disturb productivity and growth of plants. Many genes including heat shock protein (HSP), heat shock transcription factors (HSF) and chaperones, were identified and characterized in many plants to play role in increased tolerance to abiotic stress. To reveal responsive gene to heat stress, we performed RNA-seq using two Korean soybean varieties under heat stress and normal conditions. The transcripts were analyzed, and we obtained 2,458 genes including 46 co-up regulation and 55 co-down regulated genes in both soybean varieties. We also revealed HSPs, HSFs and chaperones in the differentially expressed genes using BLAST and Pfam analyzation and verified expression changes under heat stress. Finally, we find 68 genes involved in HSP, HSF, chaperones in heat responsive genes associated increasing heat tolerance. As a result, relatively small HSP families were up regulated and continuously expressed in long period heat stress. On the other hand, large molecule HSPs, HSFs and chaperonin did not response to long heat stress. The expression profiling and characterization provide invaluable information to understand heat tolerance of soybean.