中国农业科学 ›› 2026, Vol. 59 ›› Issue (4): 734-749.doi: 10.3864/j.issn.0578-1752.2026.04.003

• 作物遗传育种·种质资源·分子遗传学 • 上一篇    下一篇

甘蔗属割手密与热带种PEBP基因家族的鉴定及其开花调控功能分析

罗正英1,3(), 胡嗣桢1(), 林秀琴2,3, 胡鑫2,3, 张敏3, 徐超华2,3, 刘新龙2,3(), 曾千春1,4()   

  1. 1 云南农业大学农学与生物技术学院/云南省作物生产与智慧农业重点实验室, 昆明 650201
    2 云南省农业科学院热带作物生物育种全国重点实验室, 昆明 650205
    3 云南省农业科学院甘蔗研究所/云南甘蔗遗传改良重点实验室/农业农村部甘蔗生物学与遗传育种重点实验室(云南), 云南开远 661699
    4 云南农业大学热带作物学院, 云南普洱 665099
  • 收稿日期:2025-08-10 出版日期:2026-02-10 发布日期:2026-02-10
  • 通信作者:
    刘新龙,E-mail:
    曾千春,E-mail:
  • 联系方式: 罗正英,E-mail:zhengyluo@163.com。胡嗣桢,E-mail:18973644103@163.com。罗正英和胡嗣桢为同等贡献作者。
  • 基金资助:
    国家重点研发计划(2022YFD2301101); 云南种子种业联合实验室(202205AR070001-09); 云南省农业科学院科研项目(2024KYZX-03)

Identification and Functional Characterization of the PEBP Gene Family in Regulating Flowering Time in Saccharum spontaneum and Saccharum officinarum

LUO ZhengYing1,3(), HU SiZhen1(), LIN XiuQin2,3, HU Xin2,3, ZHANG Min3, XU ChaoHua2,3, LIU XinLong2,3(), ZENG QianChun1,4()   

  1. 1 College of Agronomy and Biotechnology, Yunnan Agricultural University/The Key Laboratory for Crop Production and Smart Agriculture of Yunnan Province, Kunming 650201
    2 State Key Laboratory of Tropical Crop Breeding, Yunnan Academy of Agricultural Sciences, Kunming, 650205
    3 Sugarcane Research Institute, Yunnan Academy of Agricultural Sciences/Yunnan Key Laboratory of Sugarcane Genetic Improvement/Key Laboratory of Sugarcane Biology and Genetic Breeding (Yunnan), Ministry of Agriculture and Rural Affairs Kaiyuan 661699, Yunnan
    4 College of Tropical Crops, Yunnan Agricultural University, Puer 665099, Yunnan
  • Received:2025-08-10 Published:2026-02-10 Online:2026-02-10

摘要:

【目的】磷脂酰乙醇胺结合蛋白(phosphatidyl ethanolamine-binding protein,PEBP)是调控植物开花的关键因子,通过协调光周期、植物激素等信号精确调控开花时间。以甘蔗原始亲本割手密(Saccharum spontaneum)和热带种(Saccharum officinarum)为材料,系统鉴定PEBP基因家族成员,分析其基本结构、进化特征与表达模式,验证关键基因功能,为解析甘蔗开花调控机制及分子育种提供理论依据。【方法】基于拟南芥和水稻PEBP基因家族成员的蛋白序列,对割手密和热带种基因组数据进行比对分析,并结合PEBP基因对应的隐马尔可夫模型文件PF01161进行筛选,最终鉴定PEBP基因家族成员;利用MEGA-X、TBtools等软件进行系统进化、基因结构、保守基序和共线性分析;通过PlantCARE数据库预测启动子顺式作用元件;结合转录组数据和qRT-PCR结果分析基因表达模式;构建FT3TFL1过表达载体并转化拟南芥,从而验证其功能。【结果】割手密和热带种分别含有23和20个PEBP基因,均分为FT-like、TFL1-like和MFT-like 3个亚家族。蛋白理化性状分析表明,割手密PEBP蛋白(151—364 aa,17.1—40.4 kDa)的变异范围显著大于热带种(170—191 aa,19.2—20.8 kDa),但均以亲水性碱性蛋白为主。保守基序分析揭示,TFL1-like亚家族高度保守,MFT-like则呈现显著多样性,其中,割手密SspMFT1.1/1.2/1.3具有独特的结构域延长。基因结构显示,FT-like外显子数目变异最大(2—5个),高于TFL1-like(3—4个)和MFT-like(4个)。进化研究发现,PEBP基因主要通过全基因组复制和片段复制扩张,热带种串联复制频率(8%)显著高于割手密(1%)。共线性分析表明,部分基因对(如SspFT5.1/SspFT5.2SoFT12.1/SoFT12.2)显示出物种特异性复制特征,割手密PEBP基因家族成员与高粱保守性更高。启动子分析显示,割手密和热带种PEBP基因均富含光响应和激素响应元件,其中,茉莉酸和脱落酸响应元件占比最高。表达分析鉴定出FT3TFL1 2个关键基因,前者表达持续上调且光周期敏感,后者呈先降后升趋势,且不受光周期调控。转基因分析证实SspFT3SoFT3促进拟南芥开花(提前约19 d),而SspTFL1SoTFL1则抑制开花。【结论】在割手密和热带种中分别鉴定了23和20个PEBP基因,分为FT-like、TFL1-like和MFT-like 3个亚家族,各亚家族在基因结构和蛋白特性方面呈现明显分化。FT3TFL1在开花进程中呈现相反的表达模式,其中,FT3对光周期响应敏感,且在热带种中表达量显著低于割手密。FT3具有促进开花的典型功能,而TFL1抑制开花。

关键词: 割手密, 热带种, PEBP基因家族, 开花调控, 表达分析, 光周期

Abstract:

【Objective】The phosphatidylethanolamine-binding protein (PEBP) family serves as pivotal regulators of plant flowering, orchestrating floral transition through the coordination of photoperiodic and hormonal signaling pathways. This study systematically characterized PEBP gene family members in the ancestral Saccharum species S. spontaneum and S. officinarum, elucidating their structural architecture, evolutionary trajectories, and expression profiles to unravel the molecular mechanisms governing flowering regulation and facilitate molecular breeding strategies.【Method】The PEBP gene family was identified by performing sequence alignment of Arabidopsis and rice PEBP protein sequences against the genomes of S. spontaneum and S. officinarum, supplemented with screening using the hidden Markov model profile PF01161. Phylogenetic reconstruction, gene structure analysis, conserved motif identification, and synteny evaluation were performed using MEGA-X and TBtools. Putative cis-regulatory elements within promoter regions were predicted via the PlantCARE database. Transcriptomic profiling coupled with qRT-PCR validation delineated expression dynamics, while functional characterization of FT3 and TFL1 genes was achieved through Arabidopsis transformation.【Result】Our analysis identified 23 and 20 PEBP genes in S. spontaneum and S. officinarum, respectively, classified into three subfamilies: FT-like, TFL1-like, and MFT-like. Protein characterization revealed greater variability in S. spontaneum PEBPs (151-364 aa; 17.1-40.4 kDa) compared to S. officinarum (170-191 aa; 19.2-20.8 kDa), though both predominantly encoded hydrophilic alkaline proteins. Conserved motif analysis demonstrated stringent conservation in TFL1-like subfamily members, while MFT-like proteins exhibited remarkable structural plasticity, exemplified by elongated PEBP domains in SspMFT1.1/1.2/1.3. Gene architecture analysis showed FT-like members possessed the highest exon variability (2-5), contrasting with TFL1-like (3-4) and MFT-like (fixed 4-exon) subfamilies. Evolutionary analysis revealed whole-genome and segmental duplications as primary expansion mechanisms, with tandem duplication frequency substantially higher in S. officinarum (8%) than S. spontaneum (1%). Syntenic analysis uncovered species-specific duplication events (e.g., SspFT5.1/SspFT5.2 and SoFT12.1/SoFT12.2) and stronger conservation between S. spontaneum and sorghum. Promoter analysis identified abundant light- and hormone-responsive elements, particularly jasmonic acid and abscisic acid response motifs. Expression profiling identified two key genes, FT3 and TFL1, with contrasting expression dynamics. FT3 displayed a sustained, photoperiod-sensitive upregulation, whereas TFL1 showed an initial decrease followed by an increase and was independent of photoperiod regulation. Transgenic validation confirmed FT3 orthologs consistently accelerated flowering (~19 days early), whereas TFL1 genes functioned as floral repressors.【Conclusion】Genomic analysis revealed 23 and 20 PEBP genes in S. spontaneum and S. officinarum, respectively, phylogenetically clustered into three well-defined subfamilies (FT-like, TFL1-like, and MFT-like) that exhibited substantial structural and functional divergence. FT3 and TFL1 demonstrated opposite expression patterns during floral induction, with FT3 showing marked photoperiod responsiveness and significantly elevated transcript abundance in S. spontaneum relative to S. officinarum. Transgenic functional analysis confirmed that FT3 typically promotes flowering, whereas the TFL1 gene suppresses it.

Key words: Saccharum spontaneum, Saccharum officinarum, PEBP gene family, flowering regulation, expression profiling, photoperiod