SMRT sequencing of full-length transcriptome for in-depth understanding of genes under heat stress of Rhododendron hainanense

Rhododendron is a woody plant genus of high ornamental value which is popular in landscape application all over the world. The cities' high temperature in summer greatly limits the application and geographical distribution as most of the cultivars are sensitive to heat. Rhododendron comprises more than 900 species in the world and 600 of them are growing in China. From the diversity of germplasm resources, Rhododendron hainanense was explored to have a good performance in thermostability. Therefore, we performed SMRT sequencing to provide a more complete transcriptome for heat tolerance molecular breeding. A total of 13,179,287 subreads were generated, including 699,744 ROI and 354,878 FLNC. After clustering analysis of FLNC reads and removing redundant reads, 81,945 consensus isoforms were obtained. 71,493 CDS were predicted and 61,664 SSRs were identified. Additionally, 76,825 isoforms were annotated at least in one out of five functional databases (NR, Swissprot, KEGG, KOG, Pfam), and48,167 isoforms get annotation in all five databases. Besides, 53TF families of R. hainanense were identified, such as WRKY, NAC and HSF, which are closely related to defense signaling and heat response. This full-length transcriptome database provides high quality sequences of heat-responsive genes of R. hainanens and will support the further genetic research and facilitate the exploration of heat regulatory mechanisms of Rhododendron.