Physiological functions of endosomal proteolysis

Physiological functions of endosomal proteolysis.

Endocytosis is a mechanism used by cells for uptake of macromolecules from extracellular fluid. The uptake may take place in specialized regions of the plasma membrane termed clathrincoated pits, but uptake outside these regions has been reported [1]. Macromolecules may be bound to receptors before uptake or may be present in the fluid phase of the forming endocytic vesicle. The proportion of f...

EpCAM proteolysis: new fragments with distinct functions?

EpCAM [epithelial cell adhesion molecule; CD326 (cluster of differentiation 326)] is highly expressed on epithelium-derived tumours and can play a role in cell proliferation. Recently, RIP (regulated intramembrane proteolysis) has been implicated as the trigger for EpCAM-mediated proliferative signalling. However, RIP does not explain all EpCAM-derived protein fragments. To shed light on how pr...

Endosomal proteolysis of the Ebola virus glycoprotein is necessary for infection.

Ebola virus (EboV) causes rapidly fatal hemorrhagic fever in humans and there is currently no effective treatment. We found that the infection of African green monkey kidney (Vero) cells by vesicular stomatitis viruses bearing the EboV glycoprotein (GP) requires the activity of endosomal cysteine proteases. Using selective protease inhibitors and protease-deficient cell lines, we identified an ...

Glutamine’s Physiological Functions

From the perspective of nutritional science, glutamine, like arginine, is not an essential amino acid. Nevertheless, glutamine is the most abundant amino acid in the body. Glutamine plays major roles in accelerating muscle metabolism, in preserving muscle, in promoting wound healing and in cell proliferation. It also serves as the nutritional source for gastrointestinal cells and as the major e...

Genetic Evaluation of Physiological Functions