文献类型： 外文期刊

作者： Hong, Min ¹ ; Chi, Zhuo-Heng ² ; Wang, Yong-Qing ² ; Tang, Yue-Ming ³ ; Deng, Qun-Xian ² ; He, Ming-Yang ¹ ; Wang, Ri- ¹ ;

作者机构： 1.Southwest Univ, Chinese Acad Agr Sci, Citrus Res Inst, Chongqing 400712, Peoples R China

2.Sichuan Agr Univ, Coll Hort, Chengdu 611130, Peoples R China

3.Sichuan Acad Agr Sci, Inst Agroprod Proc Sci & Technol, Chengdu 610066, Peoples R China

关键词： loquat; carotenoids; CYC-B gene; virus-induced gene silencing (VIGS)

期刊名称：BIOMOLECULES （ 影响因子：4.879； 五年影响因子：5.362 ）

ISSN：

年卷期： 2019 年 9 卷 12 期

页码：

收录情况： SCI

摘要： Carotenoids are the principal pigments in the loquat. Although the metabolic pathway of plant carotenoids has been extensively investigated, few studies have been explored the regulatory mechanisms of loquat carotenoids because knowledge of the loquat genome is incomplete. The chromoplast-specific lycopene beta-cyclase gene (CYC-B) could catalyze cyclization of lycopene to beta-carotene. In this study, the differential accumulation patterns of loquat with different colors were analyzed and virus-induced gene silencing (VIGS) was utilized in order to verify CYC-B gene function. Using a cloning strategy of homologous genes, a CYC-B gene orthologue was successfully identified from the loquat. At a later stage of maturation, CYC-B gene expression and carotenoids concentrations in the 'Dawuxing' variety were higher than in 'Chuannong 1-5-9 ', possibly leading to the difference in pulp coloration of loquat. Interference of CYC-B gene expression in the loquat demonstrated clear visual changes. The green color in negative control fruits became yellow, while TRV2-CYC-B silenced fruits remained green. CYC-B gene expression and total carotenoid content in the pulp decreased by 32.5% and 44.1%, respectively. Furthermore, multiple key genes in the carotenoid metabolic pathway synergistically responded to downregulation of CYC-B gene expression. In summary, we provide direct evidences that CYC-B gene is involved in carotenoid accumulation and coloration in the loquat.