Guangxi Academy of Agricultural Sciences, Nanning, 530007, China.
Guangxi Normal University for Nationalities, Chongzuo, 532200, China.
BMC Plant Biol. 2022 Apr 12;22(1):193. doi: 10.1186/s12870-022-03550-8.
Hami melon (Cucumis melo var. saccharinus) is a popular fruit in China because of its excellent taste, which is largely determined by its physicochemical characteristics, including flesh texture, sugar content, aroma, and nutrient composition. However, the mechanisms by which these characteristics are regulated have not yet been determined. In this study, we monitored changes in the fruits of two germplasms that differed in physicochemical characteristics throughout the fruit development period.
Ripe fruit of the bred variety 'Guimi' had significantly higher soluble sugar contents than the fruit of the common variety 'Yaolong.' Additionally, differences in fruit shape and color between these two germplasms were observed during development. Comparative transcriptome analysis, conducted to identify regulators and pathways underlying the observed differences at corresponding stages of development, revealed a higher number of differentially expressed genes (DEGs) in Guimi than in Yaolong. Moreover, most DEGs detected during early fruit development in Guimi were associated with cell wall biogenesis. Temporal analysis of the identified DEGs revealed similar trends in the enrichment of downregulated genes in both germplasms, although there were differences in the enrichment trends of upregulated genes. Further analyses revealed trends in differential changes in multiple genes involved in cell wall biogenesis and sugar metabolism during fruit ripening.
We identified several genes associated with the ripening of Hami melons, which will provide novel insights into the molecular mechanisms underlying the development of fruit characteristics in these melons.
哈密瓜（Cucumis melo var. saccharinus）因其口感极佳而在中国广受欢迎，其理化特性，包括果肉质地、含糖量、香气和营养成分，在很大程度上决定了其口感。然而，这些特性的调节机制尚未确定。在这项研究中，我们监测了两个在理化特性上存在差异的种质果实在整个果实发育期间的变化。
与普通品种“雅龙”相比，培育品种“贵蜜”的成熟果实具有显著更高的可溶性糖含量。此外，在发育过程中观察到这两个种质之间的果实形状和颜色存在差异。为了鉴定在发育的相应阶段观察到的差异背后的调控因子和途径，我们进行了比较转录组分析，结果显示贵蜜中的差异表达基因（DEGs）数量明显高于雅龙。此外，在贵蜜早期果实发育过程中检测到的大多数 DEGs 与细胞壁生物发生有关。鉴定出的 DEGs 的时间分析显示，尽管上调基因的富集趋势存在差异，但在两个种质中下调基因的富集趋势相似。进一步的分析揭示了在果实成熟过程中参与细胞壁生物发生和糖代谢的多个基因的差异变化趋势。
我们鉴定了与哈密瓜成熟相关的几个基因，这将为这些瓜类果实特征发育的分子机制提供新的见解。
