Multivesicular endosomes MVEs are elaborate intracellular or

Multivesicular endosomes (MVEs) are elaborate intracellular organelles found along the endosome-lysosome pathway. The MVE is an intermediate compartment that is formed from endosomes by invagination of the limiting endosomal membrane. Please give distinct examples of MVE functions in normal and pathological conditions. Explain them briefly.

Solution

MVEs are complex intracellular organelles that function in endocytosis. Appropriately sorted proteins such as epidermal growth factor receptor are incorporated into MVEs before transport to the lysosomal compartment where degradation occurs.

The first studies suggesting the MVEs have a role on protein sequestration was done using reticulocytes. Transferrin receptors are sequestered into MVEs when they are no longer needed by the cell and subsequently shed into the extracellular compartment. B cells, T cells, and dendritic cells also release vesicles derived from multivesicular endosomes.

During the virus infection, these MVEs are sites for the virus assembly. The observation is that virus budding requires Vps4 and TSG101 which are important components for entry into MVEs. The virus may use the MVE as a platform for virus budding and assembly into the MVE with subsequent access to the exterior environment by fusion with plasma membrane.