以铁观音芽叶为材料,验证从茶树转录组数据库中筛选到的1条牻牛儿基牻牛儿基焦磷酸合成酶(GGDPS)的编码全长序列cDNA.该cDNA全长1661 bp,含有1个1137 bp完整的开放阅读框,命名为CsGGDPS.该基因编码378个氨基酸,氨基酸序列具有类异戊二烯合成酶家族的5个保守域和2个特征功能域;序列分析显示,该cDNA与其他植物GGDPS高度保守,与三七(Panax notoginseng)的亲缘关系最近.CsGGDPS属于不稳定、亲水蛋白,可能定位到叶绿体中,不存在跨膜结构,无信号肽,发生磷酸化的位点可能有20个;二级结构主要由 α-螺旋构成,三级结构与拟南芥GGPPS11匹配度最高.实时荧光定量PCR结果表明,在茶树发育过程和不同叶位CsGGDPS的表达量随芽叶成熟度的增加呈上升趋势,随着做青过程的进行,CsGGDPS的表达量逐渐升高;CsGGDPS在父本黄旦、母本铁观音和子一代金观音中均有表达,但表达量存在差异.%A full-length cDNA sequence encoding geranylgeranyl diphosphate synthase (GGDPS) was isolated from transcriptome database of tea plant, cloned from C. sinensis cv. Tieguanyin and named as CsGGDPS. The cDNA length of CsGGDPS was 1661 bp, with an open reading frame (ORF) of 1137 bp and deduced protein of 378 amino acids. The protein was deduced to contain 5 conserved domains with 2 functional domains of Isoprenoid-Biosyn-C1 superfamily. The sequence analysis showed that CsGGDPS was highly conserved and had the closest genetic relationship with Panax notoginseng. CsGGDPS was an instability and hydrophilic protein, which was predicted to be located in chloroplast but with no transmembrane structure and signal peptide. There were 20 phosphorylation sites within the polypeptide chain. Alpha helix was predicted to be the major secondary structure of CsGGDPS. The three-dimension structure of CsGGDPS was highly similar to GGPPS11 from Arabidopsis thaliana. The quantitative real-time PCR showed that CsGGDPS expression was increased during the developmental process and increased with the age of tea leaves. Meanwhile, its expression was also enhanced during the Zuoqing procedure. CsGGDPS was ubiquitously expressed in the C. sinensis cv. Huangdan, cv. Tieguanyin and their first filial generation cv. Jinguanyin, but with different expression levels.
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