海岛棉转录因子基因GbTCP27的克隆及表达特性分析

Cloning and expression characterization analysis of the Gossypium barbadense transcription factor gene GbTCP27ZHENG Kai, QU Yanying, Ni Zhiyong, CAI Yongsheng, SHI Yingying, CHEN Quanjia*

关键词:  海岛棉  TCP  转录因子  亚细胞定位  表达特性

Key words:  Gossypium barbadense  TCP  transcription factor  subcellular localization  expression characteristics

摘要:

为探究转录因子GbTCP27在棉花纤维发育中的作用，使用RT-PCR技术从海岛棉‘新海21号’中克隆GbTCP27，并对其进行生物信息学和表达特性分析。结果表明，该基因有1个1 017 bp的开放阅读框，编码338个氨基酸，预测分子量约为35.37 ku，等电点为9.08，分子式为C₁₅₄₉H₂₅₁₁N₄₃₉O₄₈₃S₁₁，序列中含有一个高度保守的TCP结构域；氨基酸序列对比表明，海岛棉GbTCP27基因在进化过程中是相当保守的，蛋白序列与其他植物中的TCP蛋白序列有较高的一致性；亚细胞定位结果显示，GbTCP27属于核定位基因，推测GbTCP27可能在复制和转录的过程中发挥作用；进化树分析表明，海岛棉GbTCP27基因与亚洲棉GaTCP9基因分布在同一分支上；实时荧光定量PCR表明，GbTCP27基因在开花当天的花瓣和开花当天的胚珠中表达量最高；综上所述，GbTCP27转录因子可能参与棉花纤维起始期胚珠表皮细胞的发育。

Abstract:

To study the role of the transcription factor GbTCP27 in cotton fiber development, RT-PCR was used to clone GbTCP27 from the island cotton ‘Xinhai 21'. The island cotton GbTCP27 gene has a 1 017 bp open reading frame encoding 338 amino acids with a predicted molecular weight of approximately 35. 37 ku, an isoelectric point of 9. 08, and a molecular formula of C₁₅₄₉H₂₅₁₁N₄₃₉O₄₈₃S₁₁. The sequence contains a highly conserved TCP domain. The amino acid sequence comparison showed that the GbTCP27 gene of the sea-island cotton was quite conserved during the evolution process, and the protein sequence was highly consistent with the TCP protein sequence in other plants. Subcellular localization results showed that GbTCP27 belonged to nuclear localization gene. It is predicted that GbTCP27 might play a role in the process of replication and transcription. Phylogenetic tree analysis indicated that the island cotton GbTCP27 gene was distributed on the same branch as the Asian cotton GaTCP9 gene. Real-time PCR showed that the GbTCP27 gene was expressed most in the ovule on the day of flowering and on the day of flowering. In summary these results suggest that GbTCP27 transcription factor may be involved in the development of ovule epidermal cells in cotton fiber initiation stage.