Chromosome-scale genome assembly ofCamellia crapnellianaprovides insights into the fatty acid biosynthesis

Abstract

Camellia crapnelliana Tutch., belonging to the Theaceae family, is an excellent landscape tree species with high ornamental value. It is particularly an important woody oil-bearing plant with high ecological, economic, and medicinal values. Here, we first report the chromosome-scale reference genome of C. crapnelliana with integrated technologies of SMRT, Hi-C and Illumina sequencing platforms. The genome assembly had a total length of ~2.94 Gb with contig N50 of ~67.5 Mb, and ~96.34% of contigs were assigned to 15 chromosomes. In total, we predicted 37,390 protein-coding genes, ~99.00% of which were functionally annotated. Comparative genomic analysis showed that the C. crapnelliana genome underwent a whole-genome duplication event shared across the Camellia species and an γ -WGT event that was shared by all core eudicot plants. Furthermore, we identified the major genes involved in the biosynthesis of oleic acids and terpenoids in C. crapnelliana. The chromosome-scale genome of C. crapnelliana will become valuable resources for understanding the genetic basis of the fatty acid biosynthesis, and greatly facilitate the exploration and conservation of C. crapnelliana.