title: Plant science. Biosynthesis, regulation, and domestication of bitterness in cucumber.
abstract: Cucurbitacins are triterpenoids that confer a bitter taste in cucurbits such as cucumber, melon, watermelon, squash, and pumpkin. These compounds discourage most pests on the plant and have also been shown to have antitumor properties. With genomics and biochemistry, we identified nine cucumber genes in the pathway for biosynthesis of cucurbitacin C and elucidated four catalytic steps. We discovered transcription factors Bl (Bitter leaf) and Bt (Bitter fruit) that regulate this pathway in leaves and fruits, respectively. Traces in genomic signatures indicated that selection imposed on Bt during domestication led to derivation of nonbitter cucurbits from their bitter ancestors.
authors.affiliation: Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Key Laboratory of Biology and Genetic Improvement of Horticultural Crops of the Ministry of Agriculture, Sino-Dutch Joint Laboratory of Horticultural Genomics, Beijing 100081, China. Agricultural Genomic Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen 518124, China.
authors.forename: Yi
authors.initials: Y
authors.lastname: Shang
authors.affiliation: Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Key Laboratory of Biology and Genetic Improvement of Horticultural Crops of the Ministry of Agriculture, Sino-Dutch Joint Laboratory of Horticultural Genomics, Beijing 100081, China. College of Life Sciences, Nanjing Agricultural University, Nanjing 210095, China.
authors.forename: Yongshuo
authors.initials: Y
authors.lastname: Ma
authors.affiliation: Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Key Laboratory of Biology and Genetic Improvement of Horticultural Crops of the Ministry of Agriculture, Sino-Dutch Joint Laboratory of Horticultural Genomics, Beijing 100081, China. Horticulture and Landscape College, Hunan Agricultural University, National Chinese Medicinal Herbs Technology Center, Changsha 410128, China.
authors.forename: Yuan
authors.initials: Y
authors.lastname: Zhou
authors.affiliation: Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Key Laboratory of Biology and Genetic Improvement of Horticultural Crops of the Ministry of Agriculture, Sino-Dutch Joint Laboratory of Horticultural Genomics, Beijing 100081, China. College of Life Sciences, Nanjing Agricultural University, Nanjing 210095, China.
authors.forename: Huimin
authors.initials: H
authors.lastname: Zhang
authors.affiliation: Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China.
authors.forename: Lixin
authors.initials: L
authors.lastname: Duan
authors.affiliation: Hunan Vegetable Research Institute, Hunan Academy of Agricultural Sciences, Changsha 410125, China.
authors.forename: Huiming
authors.initials: H
authors.lastname: Chen
authors.affiliation: Horticulture and Landscape College, Hunan Agricultural University, National Chinese Medicinal Herbs Technology Center, Changsha 410128, China.
authors.forename: Jianguo
authors.initials: J
authors.lastname: Zeng
authors.affiliation: Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Key Laboratory of Biology and Genetic Improvement of Horticultural Crops of the Ministry of Agriculture, Sino-Dutch Joint Laboratory of Horticultural Genomics, Beijing 100081, China.
authors.forename: Qian
authors.initials: Q
authors.lastname: Zhou
authors.affiliation: Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Key Laboratory of Biology and Genetic Improvement of Horticultural Crops of the Ministry of Agriculture, Sino-Dutch Joint Laboratory of Horticultural Genomics, Beijing 100081, China.
authors.forename: Shenhao
authors.initials: S
authors.lastname: Wang
authors.affiliation: Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Key Laboratory of Biology and Genetic Improvement of Horticultural Crops of the Ministry of Agriculture, Sino-Dutch Joint Laboratory of Horticultural Genomics, Beijing 100081, China. College of Life Sciences, Wuhan University, Wuhan 430072, China.
authors.forename: Wenjia
authors.initials: W
authors.lastname: Gu
authors.affiliation: Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Key Laboratory of Biology and Genetic Improvement of Horticultural Crops of the Ministry of Agriculture, Sino-Dutch Joint Laboratory of Horticultural Genomics, Beijing 100081, China. College of Life Sciences, Nanjing Agricultural University, Nanjing 210095, China.
authors.forename: Min
authors.initials: M
authors.lastname: Liu
authors.affiliation: Institute of Microbiology, Chinese Academy of Sciences, Beijing 100190, China.
authors.forename: Jinwei
authors.initials: J
authors.lastname: Ren
authors.affiliation: Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Key Laboratory of Biology and Genetic Improvement of Horticultural Crops of the Ministry of Agriculture, Sino-Dutch Joint Laboratory of Horticultural Genomics, Beijing 100081, China.
authors.forename: Xingfang
authors.initials: X
authors.lastname: Gu
authors.affiliation: Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Key Laboratory of Biology and Genetic Improvement of Horticultural Crops of the Ministry of Agriculture, Sino-Dutch Joint Laboratory of Horticultural Genomics, Beijing 100081, China.
authors.forename: Shengping
authors.initials: S
authors.lastname: Zhang
authors.affiliation: Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Key Laboratory of Biology and Genetic Improvement of Horticultural Crops of the Ministry of Agriculture, Sino-Dutch Joint Laboratory of Horticultural Genomics, Beijing 100081, China.
authors.forename: Ye
authors.initials: Y
authors.lastname: Wang
authors.affiliation: School of Pharmacy, Nihon University, Tokyo 101-8308, Japan.
authors.forename: Ken
authors.initials: K
authors.lastname: Yasukawa
authors.affiliation: Laboratory of Plant Physiology, Wageningen University, Wageningen 6700, Netherlands.
authors.forename: Harro J
authors.initials: HJ
authors.lastname: Bouwmeester
authors.affiliation: Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China.
authors.forename: Xiaoquan
authors.initials: X
authors.lastname: Qi
authors.affiliation: Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Key Laboratory of Biology and Genetic Improvement of Horticultural Crops of the Ministry of Agriculture, Sino-Dutch Joint Laboratory of Horticultural Genomics, Beijing 100081, China.
authors.forename: Zhonghua
authors.initials: Z
authors.lastname: Zhang
authors.affiliation: Department of Plant Biology, College of Biological Sciences, University of California, Davis, CA 95616, USA.
authors.forename: William J
authors.initials: WJ
authors.lastname: Lucas
authors.affiliation: Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Key Laboratory of Biology and Genetic Improvement of Horticultural Crops of the Ministry of Agriculture, Sino-Dutch Joint Laboratory of Horticultural Genomics, Beijing 100081, China. Agricultural Genomic Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen 518124, China. huangsanwen@caas.cn.
authors.forename: Sanwen
authors.initials: S
authors.lastname: Huang
mesh_terms: D001483:Base Sequence; D018553:Cucumis sativus / Q000235:genetics / Q000378:metabolism*; D005638:Fruit / Q000235:genetics / Q000378:metabolism*; D018506:Gene Expression Regulation, Plant; D018745:Genome, Plant; D008969:Molecular Sequence Data; D018515:Plant Leaves / Q000235:genetics / Q000378:metabolism*; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism*; D013649:Taste; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism*; D014315:Triterpenes / Q000138:chemical synthesis / Q000378:metabolism*
chemical_list: D010940:Plant Proteins; D014157:Transcription Factors; D014315:Triterpenes; C474429:cucurbitacin C