摘要
【目的】类萌发素蛋白(germin-like proteins,GLPs)是一种广泛存在的植物糖蛋白,属于cupin超家族,在植物响应非生物和生物胁迫中起着重要作用。对GLPs基因进行生物信息学特征与表达分析,为揭示茶树抗病虫等生物胁迫机理提供参考。【方法】前期从茶橙樱螨刺吸转录组中筛选出2个差异表达的类萌发素蛋白基因CsGLP1和CsGLP2,对其进行理化特性、蛋白质修饰和亚细胞定位预测、结构和启动子序列、氨基酸序列特征分析蛋白质二级结构、进化树、蛋白质高级结构以及不同组织和生物胁迫处理下的表达模式分析。【结果】CsGLP1的开放阅读框为756 bp,编码251个氨基酸,分子量为28.68 kD,等电点为5.195;CsGLP2的开放阅读框为606 bp,编码201个氨基酸,分子量为21.05 kD,等电点为8.316。另外,CsGLP1和CsGLP2在氨基酸组成上具有较大差异,预测分析表明它们均可能发生磷酸化、糖基化等修饰。CsGLP1和CsGLP2都具有信号肽输出位点,为分泌蛋白。在BoxA(QDFCVAD)、BoxB(G--P-H-HPRATEXXX--G)和BoxC(GXXHFQN-G)上具有较高的保守性。进化树分析显示,CsGLP1和CsGLP2属于不同的亚家族。蛋白结构分析表明它们的二级结构主要以无规则卷曲为主,都具有典型的同源六聚体三级结构。CsGLP1和CsGLP2的启动子中含有多种逆境胁迫响应相关的元件。qRT-PCR检测分析发现,CsGLP1和CsGLP2具有组织表达差异性,CsGLP2的表达在茶尺蠖取食后显著上调。【结论】茶树类萌发素蛋白基因CsGLP1和CsGLP2在不同病害处理阶段可能具有不同的响应功能,结合其在这3种生物胁迫下的表达水平变化,推测CsGLP2在茶树响应刺吸式害虫中可能发挥了重要的功能,为深入研究GLPs基因在茶树抗逆等方面的功能奠定基础。
【Objective】Bioinformatics and expressions of genes related to the germin-like proteins(GLPs)of cupin superfamily,which are diverse and ubique glycoproteins that play a fundamental role in the response of plants to abiotic and biotic stresses, were studied. 【Method】Two genes of GLPs, CsGLP1 and CsGLP2, selected from our previous transcriptome data on Acaphylla theae-infected tea plants were analyzed for the physicochemical properties, modification, subcellular localization, structure, promoter sequence, and amino acid sequence of the proteins. Secondary and tertiary structures, evolutionary tree, and expressions in tissues under stresses of the genes were determined. 【Result】The open reading frame of CsGLP1 was 756 bp encoding 251 amino acids with a molecular weight of 28.68 kD and an isoelectric point of 5.195, while that of CsGLP2 was 606 bp encoding 201 amino acids with a molecular weight of 21.05 kD and an isoelectric point of 8.316. Significant differences in amino acid composition were found between the two proteins. Both genes were subject to modifications such as phosphorylation and glycosylation. The signal peptide sites on them were secretory proteins that were highly conserved on Box A (qDFCVAD), Box B (G--P-H- HpraTexxx--G), and Box C (GXXHFQ-N-G) with sequences highly similar to those of homologous proteins in other plants. With phylogenetic trees belonging to different subfamilies, the genes had secondary structures largely random coils, and tertiary typical homohexamers. The promoters of CsGLP1 and CsGLP2 contained various cis-elements relating to stress response. The gene expressions were tissue-specific and significantly up-regulated by invasion of Ectropis obliqua. 【Conclusion】CsGLP1 and CsGLP2 in tea plants were identified and analyzed bioinformatically to reveal the different functions in response to pathogenic attacks at different stages. The differentiated gene expressions under 3 artificially imposed biotic stresses led to the speculation of an important role CsGLP2 might play for tea plant in response to the invasion of stinging insects.
作者
吴宗杰
林宏政
欧晓西
孙云
WU Zong-jie;LIN Hong-zheng;OU Xiao-xi;SUN Yun(College of Horticulture,Fujian Agriculture and Forestry University/Key Laboratory of Tea Science in Universities of Fujian Province,Fuzhou 350002)
出处
《茶叶学报》
2023年第6期13-25,共13页
Acta Tea Sinica
基金
国家现代农业产业技术体系资助(CARS-19)
福建农林大学茶产业链科技创新与服务体系建设项目(K1520005A06)
福建张天福茶叶发展基金会科技创新基金(FJZTF01)。
关键词
茶树
类萌发素基因
生物信息学分析
基因表达
生物胁迫
Tea plant
germinin-like protein gene
bioinformatics analysis
gene expression
biotic stress
