title: Effect of the citrus lycopene β-cyclase transgene on carotenoid metabolism in transgenic tomato fruits.
abstract: Lycopene β-cyclase (LYCB) is the key enzyme for the synthesis of β-carotene, a valuable component of the human diet. In this study, tomato constitutively express Lycb-1 was engineered. The β-carotene level of transformant increased 4.1 fold, and the total carotenoid content increased by 30% in the fruits. In the transgenic line, the downstream α-branch metabolic fluxes were repressed during the three developmental stages while α-carotene content increased in the ripe stage. Microarray analysis in the ripe stage revealed that the constitutive expression of Lycb-1 affected a number of pathways including the synthesis of fatty acids, flavonoids and phenylpropanoids, the degradation of limonene and pinene, starch and sucrose metabolism and photosynthesis. This study provided insight into the regulatory effect of Lycb-1 gene on plant carotenoid metabolism and fruit transcriptome.
authors.affiliation: Key Laboratory of Horticultural Plant Biology of Ministry of Education, Huazhong Agricultural University, Wuhan, China.
authors.forename: Fei
authors.initials: F
authors.lastname: Guo
authors.forename: Wenjing
authors.initials: W
authors.lastname: Zhou
authors.forename: Jiancheng
authors.initials: J
authors.lastname: Zhang
authors.forename: Qiang
authors.initials: Q
authors.lastname: Xu
authors.forename: Xiuxin
authors.initials: X
authors.lastname: Deng
mesh_terms: D000081008:Bicyclic Monoterpenes; D001643:Bridged Bicyclo Compounds / Q000737:chemistry; D002241:Carbohydrates / Q000737:chemistry; D002338:Carotenoids / Q000737:chemistry; D053138:Cyclohexenes / Q000737:chemistry; D005818:Genetic Engineering / Q000379:methods; D019753:Intramolecular Lyases / Q000235:genetics* / Q000378:metabolism*; D000077222:Limonene; D018551:Solanum lycopersicum / Q000235:genetics*; D008957:Models, Genetic; D039821:Monoterpenes / Q000737:chemistry; D020411:Oligonucleotide Array Sequence Analysis; D010788:Photosynthesis; D030821:Plants, Genetically Modified; D060888:Real-Time Polymerase Chain Reaction / Q000379:methods; D013395:Sucrose / Q000737:chemistry; D013729:Terpenes / Q000737:chemistry; D014158:Transcription, Genetic; D019076:Transgenes
chemical_list: D000081008:Bicyclic Monoterpenes; D001643:Bridged Bicyclo Compounds; D002241:Carbohydrates; D053138:Cyclohexenes; D039821:Monoterpenes; D013729:Terpenes; D002338:Carotenoids; C010789:beta-pinene; D013395:Sucrose; D000077222:Limonene; D019753:Intramolecular Lyases; C070925:lycopene cyclase-isomerase