14-ERASynBio: Synthetic Glycobiology - new strategies to build and functionalise proto-cells and proto-tissues

基于巨大单层囊泡(GUV)的原始细胞的研究取得了很大进展。然而，所有活细胞仍将被整合到这样的系统中的一个基本功能元件是糖萼。这种复杂碳水化合物的涂层从细胞膜延伸到100 nm，并提供了一层粘附层，调节不同细胞类型、病毒和信号分子之间的相互作用。在大多数情况下，这些相互作用涉及特定的碳水化合物结合蛋白(凝集素)，这些蛋白可能是可溶的，也可能是膜结合的。例如，受精是由卵子表面的特定碳水化合物附着在精子头部的特定凝集素启动的。蛋白质-碳水化合物的相互作用也介导了许多细菌、病毒和细菌毒素的内吞作用，这些细菌、病毒和细菌毒素附着在细胞膜上的特定糖脂上。因此，蛋白质-碳水化合物的相互作用提供了一种实现细胞黏附和细胞进入的一般策略。在这个项目中，我们将设计和创造一个模板化工具箱，由合成的杯状花环成分和工程凝集素组成，它们将附着在脂膜上，实现可逆的原始细胞黏附，并结合到病毒样颗粒中，以介导原始细胞的进入。这一方法将通过构建包含“原细胞器”的原始细胞以及组装和改造“原始组织”来举例说明，在“原始组织”中，多种类型的原始细胞以预先定义的方式结合在一起，以创建更复杂的系统。

Great advances have been made in the development of proto-cells based on giant unilamellar vesicles (GUVs). However, one essential functional element of all living cells still to be incorporated into such systems is a glycocalyx. This coating of complex carbohydrates extends up to 100 nm from the cell membrane and provides an adhesive layer that mediates interactions between different cell types, viruses and signalling molecules. In most cases, these interactions involve specific carbohydrate-binding proteins (lectins) which may be either soluble or membrane-bound. For example, fertilisation is initiated by a specific carbohydrate on the surface of the egg adhering to a specific lectin on the head of the sperm. Protein-carbohydrate interactions also mediate the endocytosis of many bacteria, viruses and bacterial toxins which stick to specific glycolipids on the cell membrane. Protein-carbohydrate interactions thus present a general strategy for enabling cell adhesion and cell entry. In this project we will design and create a modular toolbox of synthetic glcocalyx components and engineered lectins that will be attached to lipid membranes to enable reversible proto-cell adhesion and incorporated into virus-like particles to mediate proto-cell entry. The methodology will be exemplified through the construction of proto-cells that contain "proto-organelles" and the assembly and remodelling of "proto-tissues" in which multiple types of proto-cells are brought together in a pre-defined fashion to create more complex systems.