Spatiotemporal organization of thylakoid membrane biogenesis in cyanobacteria

蓝藻类囊体膜生物发生的时空组织

• 批准号: 515047629
• 负责人: Professor Dr. Jörg Nickelsen, Ph.D.
• 金额: --
• 依托单位: Arbeitsgruppe Molekulare Pflanzenwissenschaften
• 依托单位国家: 德国
• 项目类别: Research Grants
• 资助国家: 德国
• 项目状态: 未结题
• 来源: https://gepris.dfg.de/gepris/projekt/515047629?language=en
• 关键词: Spatiotemporal; organization; thylakoid; membrane; biogenesis

Most photoautotrophic bacteria contain a sophisticated intracellular membrane system named thylakoids. These internal structures represent energy transducing membranes that mediate photosynthetic electron flow and subsequent ATP generation. Accumulating evidence suggests that the biogenesis and structural dynamics of this bioenergetic machinery are highly ordered by both spatial and temporal means. Our recent findings indicate that photosystem II (PSII) biogenesis in the model cyanobacterium Synechocystis 6803 is initiated at regions where thylakoids fuse to form convergence tubules. These occasionally contact the plasma membrane at sites named “thylapses” due to their synapse-like appearance. The establishment of these biogenic membrane sub-domains requires the membrane-shaping factors CurT and AncM. CurT accumulates to high levels at heavily bended interconnected tubules which from a biogenic membrane network spanning the periphery of the entire cell. In contrast, AncM localizes only to distinct spots of the tubular system and marks thylapse regions. Thus, both serve as bona fide landmarks for the subcellular organization of thylakoid membrane biogenesis in Synechocystis 6803. By applying a blend of genetic, biochemical, and various microscopic methods this project aims at elucidating the working mode of these internal membrane sub-domains during the spatiotemporal organization of PSII biogenesis. Based on the identification of CurT and AncM as well as several PSII-related biogenesis factors, the central questions to be addressed are: (i) What determines the structural dynamics of biogenic regions? (ii) What is their precise functional organization?

大多数光合自养细菌含有一个复杂的细胞内膜系统，称为类囊体，这些内部结构代表介导光合作用电子流和随后的 ATP 生成的能量转换膜，越来越多的证据表明，这种生物能量机制的生物发生和结构动力学在空间和时间上是高度有序的。我们最近的研究结果表明，蓝藻集胞藻 6803 模型中的光系统 II (PSII) 生物发生是在以下区域启动的。类囊体融合形成会聚小管，由于它们的突触样外观，它们偶尔会在称为“thylapses”的位点接触质膜。这些生物膜子结构域的建立需要膜成形因子 CurT 和 AncM 的积累。相比之下，AncM 仅定位于管状系统的不同点。因此，两者都是集胞藻 6803 中类囊体膜生物发生的亚细胞组织的真正标志。通过应用遗传、生物化学和各种显微方法，该项目旨在阐明这些内膜的工作模式。基于 CurT 和 AncM 以及几个 PSII 相关生物发生因子的鉴定，要解决的核心问题是：（i）什么决定了生物成因区域的结构动力学？（ii）它们的精确功能组织是什么？