Translocating chain-associated membrane protein 2 (TRAM2)

Necessary for collagen type I synthesis. May couple the activity of the ER Ca(2+) pump SERCA2B with all the activity of the translocon.

This coupling may raise the local Ca(2+) concentration at the site of collagen synthesis, and a high Ca(2+) concentration may be crucial for the function of molecular chaperones involved in collagen folding. Required for proper functioning of the first transmembrane helix N-terminus of TM4SF20 into the ER lumen, may act as a ceramide sensor for controlled choice translocation (RAT) (PubMed:27499293).