Cloning and expression analysis of RhHsf24 gene in Rose (Rosa hybrida)

Rose (Rosa hybrida) is one of the most important ornamental and perfume industry crops worldwide, both economically and culturally. Abiotic stresses, such as high temperature and salt are crucial factors influencing the quality of roses. In this study, RhHsf24 was isolated from rose (R. hybrida 'Samantha'), which encodes 295 amino acids (aa). Sequence comparison with members of Arabidopsis Hsfs family revealed that this gene is most closely related to AtHsfB1; phylogenetic tree analysis with proteins from other species showed that it clusters with R. rugosa (RrHSF24), Fragaria vesca (FvHSFB1a) and Argentina anserina (AaHSF24), which are the closest relatives and belong to the class B heat shock transcription factors. RhHsf24 was localized in the nucleus. The qRT-PCR results indicated that the gene was expressed in roots, stems, leaves, flowers and buds. Expression analysis of the gene in leaves subjected to various temperatures and durations of heat stress treatment demonstrated that RhHsf24 gene expression is induced by heat stress. Under salt stress, the expression of the RhHsf24 gene generally exhibited a high level of expression with increasing concentration. The above results preliminarily clarified the biological function of RhHsf24, and provide a genetic resource and theoretical reference for the resistance breeding of roses.