Galectin-networks in apical protein trafficking

• Applicant: Professor Dr. Ralf Jacob
• Subject Area: Cell Biology
• Term: from 2014 to 2019
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 262391541

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.

• DFG Programme: Research Grants