Comparative transcriptome analysis of dioecious floral development in Trachycarpus fortunei using Illumina and PacBio SMRT sequencing

Feng Xiao, Yang Zhao, Xiurong Wang, Yuexiong Mao, Xueyan Jian

Trachycarpus fortunei is a plant with significant economic and ornamental value. Both male and female flowers of T. fortunei originate as bisexual flowers, and selective abortion occurs during floral development. However, the regulatory mechanisms underlying this process remain unclear in T. fortunei. In this study, transcriptome sequencing with Illumina and Pacific BioSciences (PacBio) single-molecule real-time (SMRT) platforms were used to investigate gene expression differences between male and female T. fortunei plants. A total of 833,137 full-length non-chimeric (FLNC) reads were obtained, and 726,846 high-quality full-length transcripts were identified. A total of 159 genes were differentially expressed between male and female flowers at all development stages. Some of the differentially expressed genes (DEGs) showed male bias, including serine/threonine-protein kinase (STPK), THUMP1 homolog and other genes. Through single-nucleotide polymorphisms(SNPs) identification, 28 genes were considered as potential sex-associated SNPs. Time-Ordered Gene Co-expression Network (TO-GCN) analysis revealed that MADS2 and MADS26 may play important roles in the development of female and male flowers T. fortune plants, respectively. These findings provide a genetic basis for flower development and differentiation in T. fortunei, and improve our understanding of the mechanisms underlying sexual differentiation in T. fortunei.