Abstract: The identification of TIFYs in Dendrobium officinale is not particularly clear. In this study, 20 D. officinale TIFY(DoTIFY) genes were identified. According to the phylogenetic analysis of TIFYs from D. officinale, Arabidopsis thaliana, Oryza sativa, Gossypium arboretum and Helianthus annuus, DoTIFYs were divided into four categories, JAZ, PPD, ZIM, and TIFY. RNA-seq analysis during the 5 stages of D. officinale protocorm development revealed 11 differentially expressed DoTIFY genes and these genes might be involved in the development of D. officinale protocorm. The qPCR analysis showed that the expression levels of DoJAZ3, 8, 5, and DoJAZ6 increased significantly during P1-P7 stages of D. officinale, indicating that they might play roles in P1-P7 stages. The result help us for the further research on the mechanism of protocorm development and related breeding improvement of D. officinale.

Key words: Dendrobium officinal Kimura et Migo, TIFY, bioinformatics analysis, RNA-seq, qPCR