CANX Human

Calnexin is a type I integral membrane protein with a large luminal domain, a single transmembrane helix, and a short cytoplasmic tail. It is involved in the folding and assembly of newly synthesized glycoproteins in the ER. Calnexin interacts with nascent glycoproteins through its lectin site, which binds to specific oligosaccharide intermediates on the folding glycoprotein .

Calnexin functions as a molecular chaperone, ensuring that glycoproteins achieve their correct conformation before they proceed to the Golgi apparatus. It retains misfolded or partially folded proteins in the ER, preventing them from being transported to the Golgi. This retention is crucial for maintaining cellular homeostasis and preventing the accumulation of misfolded proteins, which can lead to diseases .

Calnexin works in conjunction with another ER chaperone, calreticulin, to assist in protein folding. Both proteins are part of the calnexin/calreticulin cycle, which is essential for the proper folding of glycoproteins. Calnexin also interacts with other ER-resident proteins, such as ERp57, to facilitate the formation of disulfide bonds in glycoproteins .

Recombinant human calnexin is produced using various expression systems, such as HEK293 cells. The recombinant protein is often tagged with a fusion partner, such as the Fc region of human IgG1, to facilitate purification and detection. Recombinant calnexin retains its functional properties and is used in various research applications, including studies on protein folding, quality control, and ER stress responses .

Calnexin is widely used in research to study the mechanisms of protein folding and quality control in the ER. It is also used to investigate the role of ER stress in various diseases, such as neurodegenerative disorders, diabetes, and cancer. Recombinant calnexin is a valuable tool for these studies, providing insights into the molecular mechanisms underlying these processes .