Calnexin (N-terminal region) Antibody

Calnexin is a 90 kDa integral membrane protein located primarily in the endoplasmic reticulum (ER) . The structure of calnexin includes a long N-terminal calcium-binding domain that extends into the lumen of the ER and a short, acidic cytosolic domain. Calnexin associates with several cell surface proteins as they pass through the ER, and may be involved in the Ca2+-dependent retention of proteins in the ER. The amino acid sequence of calnexin is highly conserved among various species and is similar in sequence to calreticulin, another Ca2+-binding protein found in the ER. Phosphorylation may regulate the activity of the C-terminal region of Calnexin. Both proline-dependent kinase and casein kinase sites have been identified, and the phosphorylation of these sites may regulate calnexin functions involved with detection of ER protein quality control and transport.

This antibody detects a 90 kDa* protein corresponding to the apparent molecular mass of Calnexin on SDS-PAGE immunoblots of human HeLa and rat A7r5 cells. In immunocytochemistry, anti-Calnexin specifically stains endoplasmic reticulum and related vesicular structures in paraformaldehyde fixed and NP-40 permeabilized cells. This sequence has high homology to similar regions in rat and mouse Calnexin.