| 摘要: |
| 【目的】克隆调控切花菊腋芽形成的关键基因CmCUC并分析其表达特性，为菊花株型改良提供理论依据。【方法】通过基因克隆分离切花菊‘神马’的CmCUC基因序列，利用生物学信息方法分析CmCUC蛋白理化性质、蛋白结构、蛋白亲疏水性、保守结构域和启动子顺式元件，预测其跨膜结构及信号肽，利用农杆菌瞬时转化本氏烟草叶片 ，对CmCUC基因进行亚细胞定位 ，通过实时荧光定量分析CmCUC基因在菊花顶芽、腋芽、花、叶、根、茎等不同组织部位的表达特异性，明确其在不同分枝类型菊花顶芽和腋芽等组织中的表达模式，以及在‘神马’腋芽不同发育阶段的表达特性。【结果】从切花菊‘神马’中分离鉴定到1个NAC（NAM/ATAF/CUC）超家族CUC基因CmCUC，CmCUC基因全长1 017 bp。系统发育分析发现，CmCUC蛋白与罂粟PsCUC蛋白的进化关系更近；蛋白序列分析表明，CmCUC蛋白结构稳定，无信号肽且无跨膜螺旋区，为亲水性蛋白；CmCUC蛋白以无规则卷曲为主，且具有典型的NAM结构域 ，属于NAC基因家族。顺式作用元件预测分析显示 ，CmCUC基因启动子区域含有光响应元件、生长素响应元件、脱落酸响应元件和分生组织特异性表达相关元件；亚细胞定位结果显示，CmCUC基因定位于细胞核。表达分析结果显示，CmCUC基因在菊花顶芽和腋芽组织中表达量较高 ，而在花、叶、根、茎等组织中不表达或表达量较低；在不同分枝类型菊花中，CmCUC基因在顶端优势明显类型的顶芽中表达量较高；在腋芽形成的不同阶段，CmCUC基因在腋芽发育的早期阶段（腋生分生组织形成阶段）表达水平最高，随着腋芽形成，其表达水平逐渐下降。【结论】CmCUC基因属于NAC家族转录因子，可以促进切花菊的顶芽和腋芽等芽组织发育，特别是在腋芽发育过程中，其通过调控腋生分生组织的发育来促进腋芽形成。 |
| 关键词: 切花菊 腋芽发育 CmCUC基因 表达模式 |
| DOI：10. 13207/j. jnwafu. 2026. 10. 012 |
| 分类号: |
| 基金项目:国家重点研发计划项目（2023YFD1200105）；雄安新区科技计划项目；国家自然科学基金项目（32071827）；中央高校基本科研业务费专项（QNTD202503）；河北省省级科技计划项目（254X9918D） |
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| Identification and functional analysis of CmCUC gene in axillary bud development of cut chrysanthemum （Chrysanthemum × morifolium） |
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SONG Xiaojie, YUAN Qing, LUO Rujun, CONG Tianci, YANG Qingqing, YUAN Cunquan
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National Engineering Research Center for Floriculture，Beijing Key Laboratory of Ornamental Plants Germplasm Innovation & Molecular Breeding，School of Landscape Architecture，Beijing Forestry University，Beijing 100083，China
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| Abstract: |
| 【Objective】This study aimed to clone the key gene CmCUC regulating the formation of cut Chrysanthemum morifolium axillary bud and to analyze its expression characteristics，thus providing theoretical and experimental basis for molecular breeding and plant type improvement of chrysanthemum.【Method】The CmCUC gene sequence of cut C.morifolium ‘Shenma’was isolated by gene cloning. The physicochemical properties，protein structure，protein hydrophilicity and hydrophobicity，conserved domains and promoter cis-elements of CmCUC protein were analyzed by biological information method. Additionally，its transmembrane structure and signal peptide were predicted. The subcellular localization of CmCUC gene was performed by Agrobacterium-mediated transient transformation of Nicotiana tabacum leaves. The differential expression patterns of the CmCUC were investigated by qRT-PCR in various organs，including apical buds，axillary buds，flowers，leaves，roots，and stems，to clarify its expression patterns in the tissues of chrysanthemum cultivars with different branching types，along with its expression characteristics during different developmental stages of the axillary buds in‘Shenma’.【Result】 A NAC（NAM/ATAF/CUC）superfamily CUC gene，CmCUC，was isolated and identified from cut C.morifolium ‘Shenma’. The full length of the CmCUC gene was cloned to be 1 017 bp.Phylogenetic analysis showed that the CmCUC protein shared a closer evolutionary relationship with PsCUC protein of opium poppy. Protein sequence analysis revealed that CmCUC protein was a stable，hydro-philic protein lacking both a signal peptide and transmembrane helices. The CmCUC protein was mainly composed of random coils and contains a typical NAM domain，belonging to the NAC gene family. Prediction analy-sis of cis-acting ele-ments showed that the promoter region of the CmCUC gene contained light-responsive elements，auxin-responsive elements，abscisic acid-responsive elements，and meristem-specific expression related elements. Subcellular localization results demonstrated that CmCUC gene was localized in the nucleus. The expression analysis showed that CmCUC gene was highly expressed in apical buds and axillary buds，but not expressed or expressed at low levels in flowers，leaves，roots and stems. Among chrysanthemum cultivars with different branch types，the expression level of CmCUC gene was higher in the apical buds of those exhibiting strong apical dominance. At different stages of axillary bud development，the expression level of the CmCUC gene peaked at the early stage of axillary bud development（axillary meristem formation stage），and gradually decreased as the axillary bud formed.【Conclusion】The CmCUC gene belongs to the NAC family of transcription factors and can promote the development of bud tissues，including apical buds and axillary buds in cut C.morifolium.Particularly during axillary bud development，it facilitates axillary bud formation by regulating the development of axillary meristems. |
| Key words: cut Chrysanthemum×morifolium axillary bud development CmCUC gene expression pattern |
