De novo transcriptome sequencing of Camellia sasanqua and the analysis of major candidate genes related to floral traits

摘要

AbstractCamellia sasanquais one of the most famous horticultural plants inCamellia(Theaceae) due to its aesthetic appeal as landscape plant. Knowledge regarding the genetic basis of flowering time, floral aroma and color inC.?sasanquais limited, but is essential to breed new varieties with desired floral traits. Here, we described thede novotranscriptome of young leaves, flower buds and flowers ofC.?sasanqua. A total of 60,127 unigenes were functionally annotated based on the sequence similarity. After analysis, we found that two floral integrator genes,SOC1andAP1,in flowering time pathway showed evidence of gene family expansion. Compared with 1-deoxy-D-xylulose-5-phosphate pathway, some genes in the mevalonate pathway were most highly expressed, suggesting that this might represent the major pathway for terpenoid biosynthesis related to floral aroma inC.?sasanqua. In flavonoid biosynthesis pathway,PAL, CHI, DFRandANSshowing significantly higher expression levels in flowers and flower buds might have important role in regulation of floral color. The top five most transcription factors (TFs) families inC.?sasanquatranscriptome were MYB, MIKC, C3H, FAR1 and HD-ZIP, many of which have a direct relationship with floral traits. In addition, we also identified 33,540 simple sequence repeats (SSRs) in theC.?sasanquatranscriptome. Collectively, theC.?sasanquatranscriptome da