To better understand the fruit flesh coloration mechanism of peach (Prunus persica), the composition and accumulation of carotenoids were compared, the expression profile of key genes involved in carotenoid biosynthetic and catabolic pathways was performed, and the differentially expressed genes were identified using “Piqiutao” (white fruit flesh) and its mutant yellow “Piqiutao” at different fruit development stages. The results showed that the total carotenoid content in yellow “Piqiutao” was remarkably higher than that of “Piqiutao,” and the accumulation of β-cryptoxanthin, α-carotene, and β-carotene was significantly different, which was most likely caused by the differential expression of CCD4. Therefore, CCD4 may be an essential gene that causes the yellow fruit flesh of yellow “Piqiutao.” However, the coding region sequence of CCD4 was entirely identical, and the intron was inserted by a retrotransposon in “Piqiutao” and its mutant, indicating that the expression difference was not caused by the sequence mutation and retrotransposon insertion.

中文翻译：

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鉴定控制“皮秋桃”（白色果肉）及其突变体（黄色果肉）黄色/白色果肉颜色的类胡萝卜素裂解双加氧酶（CCD4）基因

为了更好地了解桃（Prunus persica）果肉着色机制，比较了类胡萝卜素的组成和积累，对参与类胡萝卜素生物合成和分解代谢途径的关键基因进行了表达谱分析，并利用“皮秋桃”鉴定了差异表达基因。 ”（白色果肉）及其不同果实发育阶段的突变黄色“皮秋桃”。结果表明，黄色“皮秋桃”类胡萝卜素的总含量明显高于“皮秋桃”，β-隐黄质、α-胡萝卜素和β-胡萝卜素的积累量也有显着差异，这很可能是由于CCD4 的差异表达。因此，CCD4可能是导致黄色“皮秋桃”果肉变黄的必需基因。然而，