Gene expression profiles of Hsp family members in different poplar taxa under cadmium stress

Abstract

Heat shock proteins (Hsps), also known as stress proteins, are expressed by living organisms. Hsp genes play key roles in the regulation of change in response to various abiotic stresses (e.g., salinity, drought, heavy metal, and extreme temperatures). In our previous studies, all Hsp family gene members were determined and named using bioinformatics approaches. We also examined their expression profiles under different stress conditions. In this study, the aim was to indicate the expression pattern of Hsp family genes under cadmium (Cd) stress in different poplar taxa which are resistant to various stresses. Firstly, transcriptome data including RNA-seq and microarray were evaluated to select Hsp gene members that were suitable targets for the cadmium stress response. Then, the expression analysis of selected genes was studied with qRT-PCR (real-time quantitative reverse transcription PCR) in different poplar taxa. Under cadmium stress conditions, the expression profiles of genes including PtsHsp-44, PtsHsp-54, PtHsp40-117, PtHsp60-06, PtHsp60-12, PtHsp70-21, PtHsp70-28, PtHsp90-02, PtHsp90-10, PtHsp90-12, PtHsp100-22, and PtHsp100-71 were observed. In the future, N.03.368A and I-214 taxa may be used for plantation in Cd-contaminated areas and studied under subsequent long-term observation. This study yielded preliminary information about Cd-stress-related molecular mechanisms that will be utilized for future projects. In addition, the genes responsive against Cd stress can be used for gene cloning and functional analyses, which could open new perspectives for improving Cd-tolerant plants or trees.