Tissue- and cell-specific transcriptomics of pyrrolizidine alkaloidbiosynthesis

吡咯里西啶生物碱生物合成的组织和细胞特异性转录组学

• 批准号: 162011329
• 负责人: Professor Dr. Dietrich Ober
• 金额: --
• 依托单位: Botanisches Institut und Botanischer Garten
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2009
• 资助国家: 德国
• 起止时间: 2008-12-31 至 2018-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/162011329?language=en
• 关键词: Tissue; cell; specific; transcriptomics; pyrrolizidine

The system of pyrrolizidine alkaloids (PAs) is a model for our studies about the evolution of pathways in plant secondary metabolism. PAs are toxic to vertebrates and insects and are believed to be selected as part of the chemical defence against herbivores. For the first pathway-specific enzyme, homospermidine synthase (HSS), we were able to show that it originated by duplication of a gene involved in primary metabolism at least five times independently during angiosperm evolution. This observation suggests that also the complete pathway of PAs has several independent origins. In the present project, we intend to identify three further enzymes of PA biosynthesis to study their evolution and compare that data with the extensive knowledge about HSS evolution. Using our knowledge about the tissue- and cell-specific expression of HSS we successfully generated transcriptome databases of various tissues of several PA-producing species. By comparing the sequence data from different tissues with bioinformatic tools, we were able to denominate sequences that encode enzymes postulated to be involved in PA biosynthesis. We will use this second phase of the project to prove the functional role of these candidate sequences in PA biosynthesis by comparing their biochemical properties with paralogous sequences that are also available in the transcriptome databases. This data in addition to phylogenetic analyses should allow conclusions about the evolution of these enzymes of PA biosynthesis.

吡咯烷碱性生物碱（PAS）的系统是我们研究植物继发代谢途径演变的模型。 PAS对脊椎动物和昆虫有毒，被认为被选为针对草食动物的化学防御的一部分。对于第一个途径特异性酶，同植物植物合酶（HSS），我们能够证明它是由于在血管生成过程中至少独立五次参与原代代谢的基因的重复。该观察结果表明，PAS的完整途径也具有多个独立的起源。在本项目中，我们打算确定三种PA生物合成的三种酶，以研究其进化，并将数据与有关HSS进化的广泛知识进行比较。利用我们对HSS组织和细胞特异性表达的了解，我们成功地生成了几种PA产生物种的各种组织的转录组数据库。通过将来自不同组织的序列数据与生物信息学工具进行比较，我们能够计算出编码被认为参与PA生物合成的酶的序列。我们将使用项目的第二阶段来证明这些候选序列在PA生物合成中的功能作用，通过将其生化特性与寄生态序列进行比较，这些序列也可以在转录组数据库中使用。除系统发育分析外，该数据还应得出关于这些PA生物合成酶进化的结论。