endosomes

An endosome is a membrane-bound compartment inside cells, roughly 300-400 nm in diameter when fully mature (WP).

Many endocytotic vesicles derived from the plasma membrane are transported to an endosome and fuse with it. Some endocytosed material passes through endosomes on its way to lysosomes.

Endosomes are, in part, responsible for the sorting of endocytosed material before transport to lysosomes. This allows some material to be returned to the plasma membrane.

Types

 clathrin-containing endosomes

• clathrin-mediated endocytosis

 clathrin-independent endosomes

• clathrin-independent endocytosis (non-clathrin endocytic pathways)
• caveosomes (caveolin-1-containing endosomes)

Video

 endosome fusion

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See also

 endocytic vesicles

References

 Gruenberg J, van der Goot FG. Mechanisms of pathogen entry through the endosomal compartments. Nat Rev Mol Cell Biol. 2006 Jul;7(7):495-504. PMID: 16773132

 Bonifacino JS, Rojas R. Retrograde transport from endosomes to the trans-Golgi network. Nat Rev Mol Cell Biol. 2006 Aug;7(8):568-79. PMID: 16936697

 Perret E, Lakkaraju A, Deborde S, Schreiner R, Rodriguez-Boulan E. Evolving endosomes: how many varieties and why?
Curr Opin Cell Biol. 2005 Aug;17(4):423-34. PMID: 15975780

 Nichols B. Caveosomes and endocytosis of lipid rafts.
J Cell Sci. 2003 Dec 1;116(Pt 23):4707-14. PMID: 14600257