目的 基于转录组与代谢组数据系统鉴定宣木瓜Chaenomeles speciose R2R3-MYB转录因子家族，筛选可能参与调控黄酮类化合物生物合成的关键候选基因。方法 构建宣木瓜不同组织的转录组与代谢组数据库，利用全长转录组数据对宣木瓜R2R3-MYB转录因子家族进行了系统鉴定，并进一步对序列特征、进化关系及组织特异性表达模式等进行分析。结果 在宣木瓜的转录组数据中经过筛选、鉴定，最终得到31个R2R3型CsMYBs基因，根据与拟南芥和月季的系统进化分析划分为11个亚组，同一亚组基因具有相似的保守基序和基因结构。儿茶素、表儿茶素等黄酮类化合物在果肉和果皮中显著富集。31个CsMYBs基因在宣木瓜不同组织中差异表达，其中CsMYB1、CsMYB21、CsMYB25等14个CsMYBs在果皮或果肉中高表达。进一步通过相关性分析，筛选出CsMYB1、CsMYB2、CsMYB14等6个与多种黄酮类化合物（如儿茶素、表儿茶素）积累呈显著正相关的候选基因，并通过RT-qPCR进行了验证。结论 首次系统鉴定了宣木瓜R2R3-MYB转录因子家族，筛选了可能参与调控黄酮类化合物生物合成的关键CsMYBs，为后续基因功能验证提供了参考，也为宣木瓜品质形成机制研究奠定了基础。

Objective To systematically identify the R2R3-MYB transcription factor family in Xuanmugua(Chaenomeles speciose) based on transcriptomic and metabolomic data, and to screen key candidate genes potentially involved in the regulation of flavonoid biosynthesis. Methods Transcriptome and metabolome databases were constructed using different tissues of C. speciosa. The R2R3-MYB transcription factor family was systematically identified based on full-length transcriptome data. Subsequently, the sequence characteristics, phylogenetic relationships, and tissue-specific expression patterns of these genes were analyzed. Results A total of 31 R2R3-type CsMYB genes were identified from the transcriptome data of C. speciosa. Based on phylogenetic analysis with Ninanjie(Arabidopsis thaliana) and Yueji (Rosa chinensis), we classified these genes into 11 subfamilies. Members within the same subfamily showed similar conserved motifs and gene structures. Flavonoids, including catechin and epicatechin, were significantly enriched in the pulp and peel. The 31 CsMYB genes exhibited differential expression patterns across various tissues of C. speciosa, among which 14 CsMYB genes, such as CsMYB1, CsMYB21, and CsMYB25, were highly expressed in the peel or pulp. Further correlation analysis revealed that six candidate genes, including CsMYB1, CsMYB2, and CsMYB14, were significantly and positively correlated with the accumulation of multiple flavonoids, such as catechin and epicatechin. These results were further validated by RT-qPCR. Conclusion This study provides the first systematic identification of the R2R3-MYB transcription factor family in C. speciosa and screens key CsMYB genes potentially involved in the regulation of flavonoid biosynthesis. These findings provide a reference for subsequent functional verification of candidate genes and lay a foundation for elucidating the molecular mechanisms underlying the quality formation of C. speciosa.

R282.12

安徽高校协同创新项目（GXXT-2023-072）；安徽中医药大学“常青藤工程”专项基金（CQT20250204）；国家中医药管理局高水平中医药重点学科中药资源学（药用植物学）建设项目（zyyzdxk-2023095）；安徽省高校杰出青年科研项目（2023AH020036）