Uncovering missing enzymatic steps in biosynthesis of the plant biopolymer sporopollenin

高等植物的繁殖成功取决于保护移动的雄配子体、花粉免受生物和非生物胁迫，包括病原体、脱水、紫外线或可变温度。植物通过将花粉包裹在称为花粉壁的坚韧外部屏障中来保护花粉，花粉壁主要由复杂的生物聚合物孢粉素组成。孢粉素是高度惰性和抗降解的，就其结构和组成而言，仍然是植物中最不了解的生物聚合物。然而，最近的研究进展的情况下，裸子植物花粉提供了第一次瞥见孢粉素的聚合结构，即使相应的生物合成途径还没有完全理解。该项目的目标是填补目前的知识空白的孢粉素生物合成的被子植物拟南芥，植物模式物种的一系列候选基因的特征，并通过分析相应的敲除线调查他们的贡献。通过共表达和转录组数据筛选出5个在孢粉素生物合成中具有不同潜在意义的候选基因。他们提出的作用，以填补缺失的步骤的孢粉素生物合成途径将使用生物化学，分子，细胞和发育的方法相结合进行评估。该项目将联合收割机结合东道国机构在植物生物化学方面的专业知识和申请人在分子生物学，细胞生物学和遗传学方面的专业知识，提供多学科的方法来解决孢粉素生物合成中的剩余问题。

Reproductive success of higher plants depends on protection of the mobile male gametophytes, the pollen, from exposure to biotic and abiotic stresses including pathogens, dehydration, UV light, or variable temperatures. Plants protect their pollen by encasing them in a tough external barrier called the pollen wall which is mainly composed of the complex biopolymer sporopollenin. Sporopollenin is highly inert and degradation-resistant, remaining the least understood biopolymer in the plants with regards to its structure and composition. Nevertheless, recent research advances in the case of gymnosperm pollen provide a first glimpse into the polymeric structure of sporopollenin even though the corresponding biosynthetic pathway is not entirely understood. The goal of this project is to fill the gaps in current knowledge of sporopollenin biosynthesis by characterizing a series of candidate genes in the angiosperm Arabidopsis thaliana, the plant model species, and investigating their contribution by analysis of the corresponding knockout lines. Five candidate genes encoding enzymes with different potential significance in sporopollenin biosynthesis were carefully selected by co-expression and transcriptome data. Their proposed role to fill in the missing steps of the sporopollenin biosynthesis pathway will be evaluated using the combination of biochemical-, molecular-, cell- and developmental approaches. This project will combine the host’s institutions expertise in plant biochemistry with the applicant’s expertise in molecular biology, cell biology and genetics providing the multidisciplinary approach to solve the remaining questions in the sporopollenin biosynthesis.