RESULTS: In this study, we characterized the R2R3-MYB gene family of Chinese cherry by genome-wide identification and compared it with those of 10 Rosaceae relatives and Arabidopsis thaliana. A total of 1490 R2R3-MYBs were classified into 43 subfamilies, which included 29 subfamilies containing both Rosaceae MYBs and AtMYBs. One subfamily (S45) contained only Rosaceae MYBs, while three subfamilies (S12, S75, and S77) contained only AtMYBs. The variation in gene numbers within identical subfamilies among different species and the absence of certain subfamilies in some species indicated the species-specific expansion within MYB gene family in Chinese cherry and its relatives. Segmental and tandem duplication events primarily contributed to the expansion of Chinese cherry R2R3-CpMYBs. The duplicated gene pairs underwent purifying selection during evolution after duplication events. Phylogenetic relationships and transcript profiling revealed that CpMYB10 and CpMYB4 are involved in the regulation of anthocyanin biosynthesis in Chinese cherry fruits. Expression patterns, transient overexpression and VIGS results confirmed that CpMYB10 promotes anthocyanin accumulation in the fruit skin, while CpMYB4 acts as a repressor, inhibiting anthocyanin biosynthesis of Chinese cherry.
CONCLUSIONS: This study provides a comprehensive and systematic analysis of R2R3-MYB gene family in Chinese cherry and Rosaceae relatives, and identifies two regulators, CpMYB10 and CpMYB4, involved in anthocyanin biosynthesis in Chinese cherry. These results help to develop and utilize the potential functions of anthocyanins in Chinese cherry.
结果:在这项研究中,我们通过全基因组鉴定鉴定了中国樱桃的R2R3-MYB基因家族,并将其与10个玫瑰科亲属和拟南芥的基因进行了比较。共有1490个R2R3-MYB被分为43个亚家族,其中包括29个亚科,同时含有玫瑰科MYBs和AtMYBs。一个亚科(S45)仅包含玫瑰科MYBs,而三个亚家族(S12,S75和S77)仅包含AtMYB。不同物种之间相同亚科中基因数量的差异以及某些物种中某些亚科的缺失表明,中国樱桃及其近缘种MYB基因家族中的物种特异性扩增。分段和串联重复事件主要促进了中国樱桃R2R3-CpMYB的扩展。复制的基因对在复制事件后的进化过程中经历了纯化选择。系统发育关系和转录谱显示,CpMYB10和CpMYB4参与了中国樱桃果实花色苷生物合成的调控。表达模式,瞬时过表达和VIGS结果证实CpMYB10促进了果皮中花青素的积累,而CpMYB4作为阻遏物,抑制樱桃花色苷的生物合成.
结论:本研究对中国樱桃和玫瑰科近缘种的R2R3-MYB基因家族进行了全面系统的分析,并确定了两个监管机构,CpMYB10和CpMYB4参与樱桃花色苷的合成.这些结果有助于开发和利用中国樱桃花色苷的潜在功能。