title: The draft genome of sweet orange (Citrus sinensis).
abstract: Oranges are an important nutritional source for human health and have immense economic value. Here we present a comprehensive analysis of the draft genome of sweet orange (Citrus sinensis). The assembled sequence covers 87.3% of the estimated orange genome, which is relatively compact, as 20% is composed of repetitive elements. We predicted 29,445 protein-coding genes, half of which are in the heterozygous state. With additional sequencing of two more citrus species and comparative analyses of seven citrus genomes, we present evidence to suggest that sweet orange originated from a backcross hybrid between pummelo and mandarin. Focused analysis on genes involved in vitamin C metabolism showed that GalUR, encoding the rate-limiting enzyme of the galacturonate pathway, is significantly upregulated in orange fruit, and the recent expansion of this gene family may provide a genomic basis. This draft genome represents a valuable resource for understanding and improving many important citrus traits in the future.
authors.affiliation: Key Laboratory of Horticultural Plant Biology (Ministry of Education), Huazhong Agricultural University, Wuhan, China.
authors.forename: Qiang
authors.initials: Q
authors.lastname: Xu
authors.forename: Ling-Ling
authors.initials: LL
authors.lastname: Chen
authors.forename: Xiaoan
authors.initials: X
authors.lastname: Ruan
authors.forename: Dijun
authors.initials: D
authors.lastname: Chen
authors.forename: Andan
authors.initials: A
authors.lastname: Zhu
authors.forename: Chunli
authors.initials: C
authors.lastname: Chen
authors.forename: Denis
authors.initials: D
authors.lastname: Bertrand
authors.forename: Wen-Biao
authors.initials: WB
authors.lastname: Jiao
authors.forename: Bao-Hai
authors.initials: BH
authors.lastname: Hao
authors.forename: Matthew P
authors.initials: MP
authors.lastname: Lyon
authors.forename: Jiongjiong
authors.initials: J
authors.lastname: Chen
authors.forename: Song
authors.initials: S
authors.lastname: Gao
authors.forename: Feng
authors.initials: F
authors.lastname: Xing
authors.forename: Hong
authors.initials: H
authors.lastname: Lan
authors.forename: Ji-Wei
authors.initials: JW
authors.lastname: Chang
authors.forename: Xianhong
authors.initials: X
authors.lastname: Ge
authors.forename: Yang
authors.initials: Y
authors.lastname: Lei
authors.forename: Qun
authors.initials: Q
authors.lastname: Hu
authors.forename: Yin
authors.initials: Y
authors.lastname: Miao
authors.forename: Lun
authors.initials: L
authors.lastname: Wang
authors.forename: Shixin
authors.initials: S
authors.lastname: Xiao
authors.forename: Manosh Kumar
authors.initials: MK
authors.lastname: Biswas
authors.forename: Wenfang
authors.initials: W
authors.lastname: Zeng
authors.forename: Fei
authors.initials: F
authors.lastname: Guo
authors.forename: Hongbo
authors.initials: H
authors.lastname: Cao
authors.forename: Xiaoming
authors.initials: X
authors.lastname: Yang
authors.forename: Xi-Wen
authors.initials: XW
authors.lastname: Xu
authors.forename: Yun-Jiang
authors.initials: YJ
authors.lastname: Cheng
authors.forename: Juan
authors.initials: J
authors.lastname: Xu
authors.forename: Ji-Hong
authors.initials: JH
authors.lastname: Liu
authors.forename: Oscar Junhong
authors.initials: OJ
authors.lastname: Luo
authors.forename: Zhonghui
authors.initials: Z
authors.lastname: Tang
authors.forename: Wen-Wu
authors.initials: WW
authors.lastname: Guo
authors.forename: Hanhui
authors.initials: H
authors.lastname: Kuang
authors.forename: Hong-Yu
authors.initials: HY
authors.lastname: Zhang
authors.forename: Mikeal L
authors.initials: ML
authors.lastname: Roose
authors.forename: Niranjan
authors.initials: N
authors.lastname: Nagarajan
authors.forename: Xiu-Xin
authors.initials: XX
authors.lastname: Deng
authors.forename: Yijun
authors.initials: Y
authors.lastname: Ruan
mesh_terms: D002678:Chimera; D002874:Chromosome Mapping; D032084:Citrus sinensis / Q000235:genetics* / Q000378:metabolism; D016000:Cluster Analysis; D019295:Computational Biology / Q000379:methods; D019143:Evolution, Molecular; D020869:Gene Expression Profiling; D018506:Gene Expression Regulation, Plant; D023061:Gene Order; D018745:Genome, Plant; D006579:Heterozygote; D059014:High-Throughput Nucleotide Sequencing; D008969:Molecular Sequence Data; D010802:Phylogeny; D014815:Vitamins / Q000378:metabolism
chemical_list: D014815:Vitamins