In biology, an endosome is a membrane-bound compartment inside cells. 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.
Annexin VI
a marker protein of hepatocytic endosomes.
PMID: 7904597
EEA1
a peripheral membrane protein associated with
the cytoplasmic face of early endosomes, controls vesicle fusion
during endocytosis, as extensively studied in non-neuronal
cells.
PMID: 17113235
ESCRT
found on tubular-vesicular endosomal
membranes rather than on endosomes themselves. The ESCRT
labeling was twice as concentrated on early and late endosomes/lysosomes
in macrophages compared with that in T cells, where it was twice
more abundant at the plasma membrane.
PMID: 17014699
Rab5
a regulatory guanosine triphosphatase that is
associated with the sorting endosome and participates in
endosomal membrane fusion reactions.
PMID: 11208157
localized on early endosomes and on the
cytoplasmic face of the plasma membrane, is involved in the
process of early endosome fusion.
PMID: 1900457
Rab7 and Lamp1
late endosomal and lysosomal membrane
markers.
PMID: 7868367
Rap1
Both GFP-tagged Rap1 and endogenous Rap1 were localized to the plasma membrane (PM) and endosomes. PMID: 14757755
Syntaxin 7
localized to late endosome compartments,
associates with Vamp 8, and Is required for late
endosome-lysosome fusion.
PMID: 10982406
Syntaxin7 as a soluble N-ethylmaleimide-sensitive
factor attachment protein receptor (SNARE) required for late
endosome-lysosome and homotypic lysosome fusion in vitro.
PMID: 10888671
Syntaxin 8
a novel member of the syntaxin family, is
localized to the early endosome marked by Rab5.
PMID: 10683148
Syntaxin 12
a member of the
syntaxin family localized to the endosome.
PMID: 9507000
VAMP-7 (vesicle-associated membrane protein-7)
a SNARE required for late endosome-lysosome fusion. PMID: 10888671
Other Endosome Makers
semiconductor quantum dots (QDs)/sheep serum
albumin (SSA) complex, therefore, can be used as a long-life and
highly photostable endosome marker.
PMID: 12615061