马瑟兰葡萄果实生长发育和品质变化的转录组分析

Transcriptome analysis of growth,development,and quality changes in Marselan grape berries

【目的】探究酿酒葡萄品种马瑟兰果实生长发育过程中的品质变化,挖掘关键的生长发育及果实品质调控基因,为马瑟兰葡萄栽培措施的精准制定和果实品质提高提供理论依据。【方法】以贺兰山东麓马瑟兰葡萄为试验材料,采集花后20 d、花后45 d、花后75 d及花后100 d不同发育阶段的葡萄果实,测量果粒横径和纵径,测定果实可溶性固形物、总糖、可滴定酸和总酚含量,并进行转录组测序分析。【结果】随着马瑟兰葡萄果实生长发育,果实色泽加深、果粒体积增大,果实可溶性固形物和总糖含量逐渐上升,可滴定酸含量逐渐下降,总酚含量在花后20 d至花后75 d期间逐渐下降而在花后75 d至花后100 d期间略有上升。从不同发育阶段葡萄果实间共筛选到33517个DEGs,花后45 d与花后20 d比较组、花后75 d与花后45 d比较组、花后100 d与花后75 d比较组共有的DEGs为3976个。GO功能注释分析结果表明,各比较组DEGs主要注释到细胞器、细胞膜、含蛋白复合物、细胞过程和代谢过程等功能条目。KEGG信号通路富集分析结果表明,氨基酸的生物合成、糖酵解/糖异生及类黄酮生物合成等是马瑟兰葡萄果实发育过程中的重要信号通路。从富集在类黄酮生物合成信号通路的DEGs中,发现查耳酮合成酶基因(CHS)和黄烷酮-3-羟化酶基因(F3H)均在花后45 d至75 d期间上调表达,F3H在花后75 d至花后100 d期间下调表达,表明CHS与F3H基因在马瑟兰葡萄果皮着色中起重要调控作用。【结论】马瑟兰葡萄生长发育过程中伴随着果实色泽加深、果粒体积增大和生化成分的动态变化。类黄酮生物合成信号通路在葡萄转色过程中起重要作用,CHS和F3H基因影响马瑟兰葡萄果实着色及品质形成。

【Objective】The study aimed to study the quality changes during the berry growth and development of wine grape variety Marselan,and to identify key genes regulating growth,development,and berry quality,providing theoretical basis for the precise formulation of cultivation practices and the improvement of berry quality.【Method】Marselan grapes from the eastern foothills of Helan Mountain were used as experimental materials.Grape berries were collected at 20,45,75 and 100 d after flowering at different developmental stages.The transverse and longitudinal diameters of the berries were measured,and the contents of soluble solids,total sugar,titratable acid and total phenolics were determined.Transcriptome sequencing analysis was also conducted.【Result】As the Marselan grape berries developed,their color deepened and berry size increased.The berry soluble solid content and total sugar content gradually rose,while the titratable acid content gradually decreased.The total phenolic content decreased from 20 d to 75 d after flowering,but slightly increased between 75 d and 100 d after flowering.A total of 33517 DEGs were identified among grape berries at different developmental stages,with 3976 DEGs shared between the comparison groups of 45 d after flowering versus 20 d after flowering,75 d after flowering versus 45 d after flowering,and 100 d after flowering versus 75 d after flowering.The results of GO functional annotation analysis showed that the DEGs in each comparison group were mainly annotated to functional categories such as organelles,cell membranes,protein-containing complexes,cellular processes and metabolic processes.The results of KEGG signaling pathway enrichment analysis showed that amino acid biosynthesis,glycolysis/gluconeogenesis and flavonoid biosynthesis were important signaling pathways during the development of Marselan grape berries.Among the DEGs enriched in the flavonoid biosynthesis signaling pathway,it was found that the chalcone synthase gene(CHS)and flavanone-3-hydroxylase gene(F3H)were up-regulated from 45 d to 75 d after flowering and down-regulated from 75 d to 100 d after flowering,suggesting that the CHS and F3H genes played important regulatory roles in the coloration of Marselan grape skin.【Conclusion】The growth and development of Marselan grapes are accompanied by the deepening of fruit color,enlargement of berry size,and dynamic changes in biochemical components.The flavonoid biosynthesis signaling pathway plays an important role in the color transition process of grapes,and the CHS and F3H genes have influence on the coloration and quality formation of Marselan grape berries.