The ins and outs of calreticulin: from the ER lumen to the extracellular space.
Calreticulin was first isolated 26 years ago. Since its discovery as a minor Ca(2+)-binding protein of the sarcoplasmic reticulum, the appreciation of its importance has grown, and it is now recognized to be a multifunctional protein, most abundant in the endoplasmic reticulum (ER). The protein has well-recognized physiological roles in the ER as a molecular chaperone and Ca(2+)-signalling molecule. However, it has also been found in other membrane-bound organelles, at the cell surface and in the extracellular environment, where it has recently been shown to exert a number of physiological and pathological effects. Here, we will focus on these less-well-characterized functions of calreticulin.
Johnson
S
S
MRC Immunochemistry Unit, University of Oxford, Oxford, UK OX1 3QU. johnson@bioch.ox.ac.uk
Michalak
M
M
Opas
M
M
Eggleton
P
P
D000818:Animals; D012634:Bodily Secretions / Q000378:metabolism; D020013:Calcium Signaling / Q000502:physiology*; D002135:Calcium-Binding Proteins / Q000378:metabolism*; D037282:Calreticulin; D002448:Cell Adhesion / Q000502:physiology; D018450:Disease Progression; D004721:Endoplasmic Reticulum / Q000378:metabolism*; D005110:Extracellular Space / Q000378:metabolism; D006706:Homeostasis / Q000502:physiology; D006801:Humans; D018832:Molecular Chaperones / Q000378:metabolism*; D015388:Organelles / Q000378:metabolism; D012261:Ribonucleoproteins / Q000378:metabolism*
D002135:Calcium-Binding Proteins; D037282:Calreticulin; D018832:Molecular Chaperones; D012261:Ribonucleoproteins