Galectin-networks in apical protein trafficking

半乳糖凝集素家族参与多种分子相互作用，并经常寡聚成半乳糖凝集素网络，仅在多细胞生物体中。上皮细胞表达不同的半乳糖凝集素同种型，并且已经显示它们中的一些在极化蛋白运输中充当顶端分选受体。它们如何组装成高分子量簇以及哪些伴侣蛋白参与将在该项目中进行研究。敲除实验和特定的半乳糖凝集素抑制剂的军火库将用于该项目的第一部分，以监测每种半乳糖凝集素同种型对极化蛋白质递送和细胞极化的贡献。潜在的分选步骤和细胞内组装成高分子量簇的半乳糖凝集素顶端囊泡招聘集中在本项目的第二部分。高分子量簇的组成将通过质谱法表征。它们的动力学将通过最先进的荧光显微镜和荧光偏振进行分析。我们的研究结果将提供深入了解顶端货物分选的机制，并解决半乳糖凝集素同种型的能力，以弥补家庭成员的损失。

The family of galectins is involved in manifold molecular interactions and frequently oligomerizes into galectin networks, exclusively in multicellular organisms. Epithelial cells express distinct galectin isotypes and it has been shown that some of them act as apical sorting receptor in polarized protein trafficking. How they assemble into high molecular weight clusters and which partner proteins are participating will be studied within this project. Knockdown experiments and an arsenal of specific galectin inhibitors will be utilized in the first part of the project to monitor the contribution of each galectin isotype on polarized protein delivery and cell polarization. The underlying sorting step and the intracellular assembly of galectins into high molecular weight clusters for apical vesicle recruitment are focused in the second part of this project. Composition of high molecular weight clusters will be characterized by mass spectrometry. Their dynamics will be analyzed by state of the art fluorescence microscopy and fluorescence polarisation. Our results will provide insights into a mechanism of apical cargo sorting and also address the competence of galectin isotypes to compensate for the loss of a family member.