浙江农业学报 ›› 2023, Vol. 35 ›› Issue (1): 90-102.DOI: 10.3969/j.issn.1004-1524.2023.01.10

• 园艺科学 • 上一篇    下一篇

基于转录组测序解析南瓜子叶黄化的分子机理

熊兴伟(), 王艺琴, 田怀志, 张素勤, 耿广东()   

  1. 贵州大学 农学院,贵州 贵阳 550025
  • 收稿日期:2022-03-30 出版日期:2023-01-25 发布日期:2023-02-21
  • 通讯作者: *耿广东,E-mail:genggd213@163.com
  • 作者简介:熊兴伟(1996—),男,侗族,贵州石阡人,硕士研究生,主要从事蔬菜生理生态与生物技术研究。E-mail:gdxxwei@163.com
  • 基金资助:
    贵州省科技计划(黔科合成果〔2021〕一般063);贵州省科技计划(黔科合成果〔2020〕1Z002号);国家重点研发计划(2021YFD1100301)

Molecular mechanisms of chlorophyll-reduced cotyledon based on transcriptome sequencing in pumpkin

XIONG Xingwei(), WANG Yiqin, TIAN Huaizhi, ZHANG Suqin, GENG Guangdong()   

  1. College of Agriculture, Guizhou University, Guiyang 550025, China
  • Received:2022-03-30 Online:2023-01-25 Published:2023-02-21

摘要:

为研究南瓜叶色黄化突变的机制,挖掘黄化相关关键基因,试验以南瓜自然黄化突变体为试材,通过高通量RNA测序(RNA-seq)对苗期子叶进行转录组分析。结果表明:从检测的26 445个表达基因中鉴定出12 687个差异表达基因(DEGs),包括6 444个上调基因,6 243个下调基因;其中2 321个DEGs是转录因子编码基因。选取14个与光合色素密切相关的DEGs进行实时荧光定量PCR(qRT-PCR)分析,发现它们的基因表达水平与转录组测序结果一致。经KEGG富集分析,发现卟啉和叶绿素(Chl)生物合成、光系统Ⅰ、光系统Ⅱ、光合作用-天线蛋白、电子传递和F型ATP酶相关基因的表达显著下调。谷氨酰-tRNA还原酶、镁离子螯合酶、叶绿素a加氧酶基因异常表达,血红素代谢相关基因表达上调抑制了Chl合成;β-胡萝卜素3-羟基酶促进了类胡萝卜素生成;另外,光合作用过程受阻也反馈抑制Chl合成,Chl合成受阻和类胡萝卜素合成受促导致南瓜叶色黄化。研究结果为南瓜黄化突变的分子机制提供了新的见解,为关键基因功能分析和南瓜育种奠定了基础。

关键词: 南瓜, 黄化突变体, 叶绿素, 转录组, 基因表达

Abstract:

In order to explore the mechanisms of chlorophyll-reduced mutation and excavate its key genes, pumpkin natural chlorophyll-reduced seedling was used as test material, and the transcriptome of the cotyledon was analyzed by high-throughput RNA sequencing (RNA-seq). The results showed that 12 687 differentially expressed genes (DEGs) were identified from 26 445 expressed genes, including 6 444 up-regulated genes and 6 243 down-regulated genes. Among them, 2 321 DEGs were transcription factor genes. Fourteen DEGs closely related to photosynthetic pigments were selected for qRT-PCR analysis. It was found that their expression level was consistent with the transcriptome data. KEGG enrichment analysis showed that the expression levels of biosynthesis of porphyrin and chlorophyll (Chl), photosystem Ⅰ, photosystem Ⅱ, photosynthesis antenna protein, electron transport, and F-type ATPase related genes were significantly down-regulated. Abnormal expression of glutamyl tRNA reductase, magnesium chelatase, and chlorophyll a oxygenase, and up-regulated expression of heme-related genes inhibited Chl synthesis. β-carotenoid 3-hydroxylase promoted carotenoid synthesis. In addition, feedback of photosynthesis inhibition also reduced Chl synthesis. The inhibition of Chl synthesis and the promotion of carotenoid synthesis led to pumpkin leaf etiolation. It laid a new foundation for the molecular analysis of pumpkin mutation and gene function.

Key words: pumpkin, chlorophyll-reduced mutant, chlorophyll, transcriptome, gene expression

中图分类号: