红心火龙果不同发育时期果肉呈色相关基因表达模式研究  

Sxpression Patterns of Flesh Color Related Genes in Red Pitaya(Hylocereus costaricensis) at Different Developmental Stages

作　　者：赵国文 贾瑞宗[2,3] 郭静远 郭安平[2,3] ZHAO Guowen;JIA Ruizong;GUO Jingyuan;GUO Anping(School of Life and College of Horticulture,Hainan University,Haikou,Hainan 570228,China;Hainan Key Laboratory for Biosafety Monitoring and Molecular Breeding in Off-Season Reproduction Regions/Institute of Tropical Bioscience and Biotech-nology,Chinese Academy of Tropical Agricultural Sciences,Haikou,Hainan 571101,China;Sanya Research Institute,Chinese Academy of Tropical Agricultural Sciences Sanya,Hainan 572024,China)

机构地区：[1]海南大学园艺学院,海南海口570228 [2]海南省南繁生物安全与分子育种重点实验室/中国热带农业科学院热带生物技术研究所,海南海口571101 [3]中国热带农业科学院三亚研究院,海南三亚572024

出　　处：《热带作物学报》2021年第11期3134-3145,共12页Chinese Journal of Tropical Crops

基　　金：海南省重大科技专项(No.ZDKJ202002);中国热带农业科学院院级创新团队项目(No.1630052017014);海南省院士团队创新中心项目。

摘　　要：火龙果属于仙人掌科量天尺属,是具有重要经济和营养价值的热带水果之一,其果实富含花青素和甜菜红素。在果实成熟后期甜菜红素的大量积累引起红心火龙果果实转色的现象。果肉色泽是评价火龙果果实品质的重要指标之一,然而其果实转色背后的基因表达调控模式并不清晰。深入研究火龙果果实发育过程中果肉颜色调控的分子机理有助于丰富火龙果品质形成的理论基础。本研究以‘美红一号’红心火龙果为实验材料,采集果实发育过程中9个不同时期的样品,通过比较转录组学共识别了96种差异表达的基因,最后分析发现15个与色素代谢通路相关的基因在果实发育不同阶段显著差异表达。GO功能富集分析发现差异表达基因主要富集在与结合活性、催化活性、转运活性和结构分子活性相关的功能分类上,且与色素代谢都有重要联系;KEGG代谢途径富集结果显示,次生代谢物合成途径、氨基酸和核酸代谢途径、酪氨酸代谢途径富集基因较多。利用实时荧光定量PCR技术对15个与色素相关的差异表达基因进行了验证,其结果与转录组分析结果一致。生理分析和转录组分析结果表明,红皮红肉火龙果发育过程中伴随大量甜菜色素的合成,且甜菜色素合成途径中DODA基因逐渐上调,在果实转色其中在P4时期明显的上升趋势,其它关键基因表达逐渐下调。本研究发掘火龙果中与果实转色相关的相关基因,为后续火龙果遗传改良提供了重要的目标基因和遗传基础。Pitaya belongs to the genus of Cactaceae and is one of the tropical fruits with important economic and nutritional value. Its fruits are rich in anthocyanins and betaine. In the late stage of fruit maturity, the accumulation of beta red pigment causes the phenomenon of red-hearted dragon fruit fruit color change. The color of the pulp is one of the important indicators to evaluate the quality of the dragon fruit. However, the gene expression regulation mode behind the color change of the fruit is unclear. In-depth study of the molecular mechanism of the color regulation of the pitaya fruit during the development of the dragon fruit will help to enrich the theoretical basis for the formation of pitaya quality. In this study, ‘Meihong No. 1’ red-hearted dragon fruit was used as the experimental material. Nine samples from different stages of fruit development were collected. A total of 96 differentially expressed genes were identified through comparative transcriptomics. Finally, 15 genes were found to be related to pigments. Genes related to metabolic pathways were significantly differentially expressed at different stages of fruit development. GO functional enrichment analysis found that differentially expressed genes were mainly enriched in functional classifications related to binding activity, catalytic activity, transport activity and structural molecule activity, and were importantly related to pigment metabolism. The results of KEGG metabolic pathway enrichment showed that there were many enriched genes in the biometabolite synthesis pathway, amino acid and nucleic acid metabolism pathway, and tyrosine metabolism pathway.Real-time fluorescent quantitative PCR technology was used to verify 15 the differentially expressed genes related to pigments, and the results were consistent with the results of transcriptome analysis. The results of physiological analysis and transcriptome analysis showed that the development of red skin and red flesh dragon fruit was accompanied by the synthesis of a large number of

关 键 词：火龙果 果实转色 转录组测序 基因挖掘 

分 类 号：S667.9[农业科学—果树学]