‘京红’桃芽变缝合线局部早熟分子机制的探究  

Molecular Mechanism Analysis of Fruit Suture Premature of‘Jinghong’Peach Mutant

作　　者：刘璐琪 申艳红[1] 宋立琴[1] 石天磊 武军凯 张立彬[1] LIU Luqi;SHEN Yanhong;SONG Liqin;SHI Tianlei;WU Junkai;ZHANG Libin(College of Horticultural Science and Technology,Hebei Normal University of Science and Technology,Hebei Key Laboratory of Horticultural Germplasm Excavation and Innovative Utilization,Qinhuangdao,Hebei 066004,China)

机构地区：[1]河北科技师范学院园艺科技学院,河北省特色园艺种质挖掘与创新利用重点实验室,河北秦皇岛066004

出　　处：《西北植物学报》2022年第10期1682-1690,共9页Acta Botanica Boreali-Occidentalia Sinica

基　　金：河北省教育厅资助项目(QN2018138);河北省高层次人才资助项目(A201901058);河北省高校园艺作物育种应用技术研发中心(YF201404)。

摘　　要：为了探究桃缝合线局部早熟的分子机制,该研究以‘京红’桃芽变(JHM)及其野生型(JHW)的果实为试材,测定分析了缝合线和果面部位的硬度、花青素含量以及差异基因的表达特征。结果显示:(1)‘京红’桃芽变比其野生型果实晚成熟约2周,芽变果实缝合线部位比果面部位局部早成熟,且提前2周时间转为红色。(2)随着果实的成熟,‘京红’桃野生型及其芽变的果实硬度逐渐降低,花青素含量逐渐升高,并均在花后66 d发生明显变化,芽变缝合线部位硬度比果面部位更低,花青素含量比果面更高。(3)在花后66 d,芽变果实的缝合线与果面部位差异表达基因数高达1889个,显著富集在代谢途径、次生代谢产物的生物合成、植物激素信号转导、苯丙素的生物合成等代谢途径;从中筛选到24个缝合线早熟相关基因,包含5个细胞壁降解相关基因,9个色素合成、调控相关基因,5个乙烯合成与转导相关基因,3个生长素应答基因和2个NAC转录因子。(4)对24个早熟相关基因中的12个差异表达基因进行荧光定量验证结果表明,基因表达趋势与转录组测序结果相一致。研究发现,桃芽变果实种仁产生的乙烯通过缝合线向周围扩散,促进缝合线部位ACS1和ACO1等基因的转录,并合成了较多乙烯,乙烯又进一步调控该部位PG、XTH33、CHS、DFR等细胞壁降解与色素合成相关基因的表达,导致该部位的果肉提前成熟。The molecular mechanism of fruit suture premature of Jinghong mutant peach was explored in this study.Peach fruits of‘Jinghong’mutant(JHM)and its wild type(JHW)were used as experimental materials.The hardness,anthocyanin,and the differential expression genes between the suture pulps and the other pulps were compared and analyzed.The results showed that:(1)the fruits of JHM ripened about two weeks later than its wild type fruits,and the suture of JHM matured earlier than the other parts of fruit,and turned red two weeks in advance.(2)The fruit hardness of JHW and JHM gradually decreased during fruit maturation,and the anthocyanin content gradually increased,and all of them changed significantly at 66 days after blooming,also the hardness of the suture was lower,but the anthocyanin content of the suture was higher than that of the other parts of fruit.(3)At 66 days after blooming,the number of differentially expressed genes reached 1889 between the suture of JHM(MSP)and the fruit surface of JHM(MP).These genes were significantly enriched in the pathway of metabolic pathways,biosynthesis of secondary metabolites,plant hormone signal transduction,phenylpropanoid biosynthesis,etc.Among them,24 differential candidate genes were screened,including 5 cell wall degradation related genes,9 pigment synthesis and regulation related genes,5 ethylene synthesis and conduction related genes,3 auxin response genes,and 2 NAC transcription factors.(4)To confirm the accuracy and reproducibility of the transcriptome analysis results,12 genes were selected for qRT-PCR validation.The expression profiles of the 12 genes have been assessed using qRT-PCR,which were consistent with the RNA-seq results,thus confirming our transcriptome analysis.The study found that ethylene diffused from the seed kernel into pulps through suture,which accelerated the expression of ASC1 and ACO1 genes,therefore more ethylene was synthesized.The synthesis of massive amount of ethylene in pulps around the suture site induced the expression of genes related

关 键 词：桃 缝合线 软化 花青素 转录组测序 

分 类 号：Q945.65[生物学—植物学] Q789[农业科学—果树学] S662.1[农业科学—园艺学]