A microscale thermophoresis instrument for measuring glycoprotein-protein interactions
Name of applicant
Katrine T. Schjoldager
Institution
University of Copenhagen
Amount
DKK 943,921
Year
2021
Type of grant
Research Infrastructure
What?
Protein-protein interactions (PPIs) are involved in most biological processes. Protein sequence and structure influence where interactions can take place and how strong they are. Post-translational modifications covalently attaches functional groups to the amino acid sidechains in a protein and thus dramatically change the number of possible proteoforms and in principle also the number of possible PPIs. Protein glycosylation is the most abundant and diverse PTM and may modulate PPIs extensively. The procured MST instrument will aid us in the process of quantifying glycosylation-dependent changes in PPIs.
Why?
We have identified site-specific glycosylation on important classes of proteins like peptide hormones (e.g. glucagon and NPY) and LDL Receptors (e.g. LDLR and LRP1). The MST will allow us to explore structure/function relationship between glycoproteins and study how glycosylation impinge on physiological relevant interactions between ligands and receptors with important implication for human metabolism, lipid and cholesterol homeostasis and neurodegenerative diseases.
How?
We have produced a panel of different recombinant glycopeptide hormones and receptors with varying glycan structures in glycoengineered mammalian cell lines. The MST can measure interaction between two or more biological components in solution and allows measuring interactions in close-to in vivo environments and complex biological fluids such as cerebrospinal fluid, serum, ascites, and cell lysates. All interactions will induce a change in the physiochemical properties of a protein and thereby its fluorescence. Using the MST we will explore our panel of glycoproteins to study the effect of glycan position and structure on peptide hormone receptor/lectin binding