Ion Transport

Calreticulin is a Calcium binding chaperone that has multiple functions both inside and outside the endoplasmic reticulum. Calreticulin is involved in the quality control of newly synthesized proteins and glycoproteins, interacting with various other ER chaperones, specifically Calnexin.

Transferrin is a protein found in the blood plasma, a glycoprotein that is specific for controlling free iron in the bodies' biological fluids. Transferrin has two binding sites that are specific for very tight and reversible iron binding. The binding of iron to transferrin can be related to pH levels, among other things, with a high binding affinity for a more acidic pH and decreasing levels as the blood pH becomes more basic. This binding affinity is the basis for the transport mechanism of Transferrin.