《植物生理学报》

谷子穗发育过程的基因表达动态分析

申慧敏¹，程金金²，王亚敏¹，吴年隆²，杨致荣²，赵雄伟^1,2,*，王兴春^1,2,*

¹山西农业大学生命科学学院, 山西晋中030801；²山西农业大学杂粮功能基因组学中心, 山西晋中030801

通信作者：赵雄伟；E-mail: xwzhao_sxau@outlook.com；王兴春；E-mail: wxingchun@sxau.edu.cn

摘　要：

穗是谷子(Setaria italica)产量和品质形成的基础, 理想的穗型是谷子遗传改良的重要目标。以新型C₄禾谷类模式植物超早熟小型谷子突变体xiaomi为对象, 利用RNA测序(RNA-Seq)技术分析了抽穗期、开花期和灌浆期3个发育时期穗中基因表达动态。结果表明, 开花期/抽穗期、灌浆期/开花期和灌浆期/抽穗期差异表达基因数分别为4 159、4 254和9 243个。其中, 光敏色素基因(PHYTOCHROME)、光周期枢纽基因(CONSTANS, CO)以及成花素基因(FLOWERING LOCUS T, FT)等在上述3个穗发育时期表达量差异显著, 而一些与淀粉合成和代谢相关的基因在谷子穗发育过程中表达量逐渐升高。此外, 还发现大量未知功能基因, 这些基因在不同穗发育时期表达量差异显著。这些基因主要涉及次生代谢物生物合成、苯丙素类化合物生物合成、植物病原菌互作、植物激素信号转导、脂肪酸合成、糖类物质合成和蜡质合成等代谢通路。本研究揭示了谷子穗发育的基因表达动态, 拟为深入解析穗发育调控的分子机制奠定基础。

关键词：谷子; 穗发育; 抽穗期; 开花期; 灌浆期; 差异表达基因

收稿：2020-12-14   修定：2021-03-17

资助：国家自然科学基金(31600289)和山西省研究生教育创新项目(2019BY067)。

Dynamic gene expression analysis during panicle development in foxtail millet

SHEN Huimin¹, CHENG Jinjin², WANG Yamin¹, WU Nianlong², YANG Zhirong², ZHAO Xiongwei^1,2,*, WANG Xingchun^1,2,*

¹College of Life Sciences, Shanxi Agricultural University, Jinzhong, Shanxi 030801, China; ²Minor Crops Functional Genomics Center, Shanxi Agricultural University, Jinzhong, Shanxi 030801, China

Corresponding author: ZHAO Xiongwei; E-mail: xwzhao_sxau@outlook.com; WANG Xingchun; E-mail: wxingchun@sxau.edu.cn

Abstract:

Panicle is crucial for the formation of yield and quality in foxtail millet (Setaria italica), and an ideal panicle architecture is a desirable target trait for genetic improvement of foxtail millet. The dynamic gene expression profiles at heading, flowering and grain-filling stages were analyzed in xiaomi, a novel C₄ model plant for cereals using RNA sequencing (RNA-Seq) technology. The results show that there were 4 159, 4 254 and 9 243 differentially expressed genes at flowering/heading, grain-filling/flowering and grain-filling/heading stages, respectively. Among these genes, the phytochrome-related genes, photoperiod hub (CONSTANS, CO) and florigen FLOWERING LOCUS T (FT) were significantly differentially expressed in the above three panicle development stages. The expression levels of the genes involved in starch synthesis and metabolism increased gradually during panicle development. In addition, a large number of unknown functional genes were significantly differentially expressed in different panicle development stages, including those involved in secondary metabolite biosynthesis, phenylpropanoid biosynthesis, plant–pathogen interaction, plant hormone signal transduction, fatty acid synthesis, carbohydrate synthesis, and wax metabolic pathways. The gene expression dynamics during panicle development was dissected in foxtail millet. We wish this study will lay a foundation for further understanding of the molecular regulation mechanism of panicle development in millet species.

Key words: foxtail millet; panicle development; heading stage; flowering stage; grain-filling stage; differentially expressed gene