目的 研究药食同源植物丝瓜Luffa cylindrica MYB（LcMYB）基因转录因子家族成员的结构和功能，鉴定参与抗褐化作用的主要成员及其作用机制。方法 基于Pfam数据库及NCBI保守结构域分析，对丝瓜全基因组水平MYB转录因子进行鉴定。通过Expasy、MEME等在线工具分析LcMYB转录因子家族蛋白理化性质、顺式作用元件及保守结构域。然后利用MEGA软件构建系统发育树，分析丝瓜与拟南芥、苹果、番茄、茄子及马铃薯等植物MYB蛋白的系统发育关系。结合2个褐化敏感程度不同的丝瓜转录组，筛选了丝瓜褐化相关的关键MYB转录因子及其靶基因。结果 全基因组水平共鉴定到449个具有相似基因结构及保守基序的MYB基因，可聚类为4个亚家族（R1_MYB、R2R3_MYB、R3_MYB和R4_MYB），并在正反链均存在可能的顺式调控元件。靶基因及基因表达分析结果显示多个MYB及其靶基因尤其是多铜氧化酶相关基因可能在鲜切丝瓜的不同褐化阶段起重要的作用，是丝瓜褐化的关键调节因子。结论 系统鉴定了LcMYB家族基因，并鉴定了可能参与丝瓜褐化的MYB基因及其靶基因，有助于进一步了解和丰富LcMYB基因家族的生理功能，并为进一步解析果实褐化调控机制，提高果实品质提供了候选基因。

Objective To study the structure and function of the Luffa cylindrica MYB (LcMYB) gene transcription factor (TF) family and identify the main member involved in anti-browning and its mechanism. Methods Based on Pfam database and NCBI conserved domain analysis, the MYB transcription factors at the whole-genome level of L. cylindrica were identified. The physicochemical properties, cis-acting elements and conserved domains of LcMYB transcription factor family proteins were analyzed by using online tools such as Expasy and MEME. Then, constructing a phylogenetic tree using MEGA software to analyze the phylogenetic relationships of MYB proteins among L. cylindrica and other plants such as Arabidopsis thaliana, apple, tomato, eggplant, and potato. Finally, the key MYB transcription factors and their target genes related to browning in L. cylindrica were screened by combining two L. cylindrica transcriptomes with different degrees of browning sensitivity. Results At the whole-genome level, a total of 449 MYB genes with similar gene structures and conserved motifs were identified, clustering into four subfamilies (R1_MYB, R2R3_MYB, R3_MYB, and R4_MYB), with potential cis-regulatory elements presenting on both the sense and antisense strands. The results of target gene analysis and gene expression analysis indicated that multiple MYB genes and their target genes, particularly those associated with multicopper oxidase, may play crucial roles in different stages of browning in fresh-cut L. cylindrica, serving as key regulatory factors for L. cylindrica browning. Conclusion This study systematically identified the LcMYB family gene and pinpointed MYB genes potentially involved in L. cylindrica browning along with their target genes, which will help to further understand and enrich the physiological functions of the LcMYB gene family, offering candidate genes for further elucidating the regulation mechanism of fruit browning and enhancing fruit quality.

R286.12

四川省应用基础研究计划项目（2021YJ0307）；成都农业科技职业学院科研课题（20ZR103）；四川省科技计划重点研发项目（2021YFN0113）； 四川省科技厅科技计划项目（2021YFN0113）