Sweet osmanthus(Osmanthus fragrans)is a very popular ornamental tree species throughout Southeast Asia and USA particularly for its extremely fragrant aroma.We constructed a chromosome-level reference genome of O.frag...Sweet osmanthus(Osmanthus fragrans)is a very popular ornamental tree species throughout Southeast Asia and USA particularly for its extremely fragrant aroma.We constructed a chromosome-level reference genome of O.fragrans to assist in studies of the evolution,genetic diversity,and molecular mechanism of aroma development.A total of over 118 Gb of polished reads was produced from HiSeq(45.1 Gb)and PacBio Sequel(73.35 Gb),giving 100×depth coverage for long reads.The combination of Illumina-short reads,PacBio-long reads,and Hi-C data produced the final chromosome quality genome of O.fragrans with a genome size of 727 Mb and a heterozygosity of 1.45%.The genome was annotated using de novo and homology comparison and further refined with transcriptome data.The genome of O.fragrans was predicted to have 45,542 genes,of which 95.68%were functionally annotated.Genome annotation found 49.35%as the repetitive sequences,with long terminal repeats(LTR)being the richest(28.94%).Genome evolution analysis indicated the evidence of whole-genome duplication 15 million years ago,which contributed to the current content of 45,242 genes.Metabolic analysis revealed that linalool,a monoterpene is the main aroma compound.Based on the genome and transcriptome,we further demonstrated the direct connection between terpene synthases(TPSs)and the rich aromatic molecules in O.fragrans.We identified three new flower-specific TPS genes,of which the expression coincided with the production of linalool.Our results suggest that the high number of TPS genes and the flower tissue-and stage-specific TPS genes expressions might drive the strong unique aroma production of O.fragrans.展开更多
基金This work was supported by research grants provided by the National Natural Science Foundation(31870695 and 31601785)the Project of Key Research and Development Plan(Modern Agriculture)in Jiangsu(BE2017375)+1 种基金the Selection and Breeding of Excellent Tree Species and Effective Cultivation Techniques(CX(16)1005)the Project of Osmanthus National Germplasm Bank,and the Top-notch Academic Programs Project of Jiangsu Higher Education Institutions.
文摘Sweet osmanthus(Osmanthus fragrans)is a very popular ornamental tree species throughout Southeast Asia and USA particularly for its extremely fragrant aroma.We constructed a chromosome-level reference genome of O.fragrans to assist in studies of the evolution,genetic diversity,and molecular mechanism of aroma development.A total of over 118 Gb of polished reads was produced from HiSeq(45.1 Gb)and PacBio Sequel(73.35 Gb),giving 100×depth coverage for long reads.The combination of Illumina-short reads,PacBio-long reads,and Hi-C data produced the final chromosome quality genome of O.fragrans with a genome size of 727 Mb and a heterozygosity of 1.45%.The genome was annotated using de novo and homology comparison and further refined with transcriptome data.The genome of O.fragrans was predicted to have 45,542 genes,of which 95.68%were functionally annotated.Genome annotation found 49.35%as the repetitive sequences,with long terminal repeats(LTR)being the richest(28.94%).Genome evolution analysis indicated the evidence of whole-genome duplication 15 million years ago,which contributed to the current content of 45,242 genes.Metabolic analysis revealed that linalool,a monoterpene is the main aroma compound.Based on the genome and transcriptome,we further demonstrated the direct connection between terpene synthases(TPSs)and the rich aromatic molecules in O.fragrans.We identified three new flower-specific TPS genes,of which the expression coincided with the production of linalool.Our results suggest that the high number of TPS genes and the flower tissue-and stage-specific TPS genes expressions might drive the strong unique aroma production of O.fragrans.
基金supported by the National Key Research and Development Program of China(2018YFD1000300)National Crop Germplasm Resources Protection of Ministry of Agriculture of China(NB2018-2130135-07).
文摘Since the publication of this article,the authors have noticed that the NCBI accession number is missing from article.
