Transmembrane Protein 221 (TMEM221)

TMEM221 is a transmembrane protein (TP) protein that goes from one side of a membrane through to the other side of the membrane. Many TPs function as gateways or "loading docks" to deny or permit the transport of specific substances across the biological membrane, to get into the cell, or out of the cell as in the case of waste byproducts. As a response to the shape of certain molecules these "freight handling" TPs may have special ways of folding up or bending that will move a substance through the biological membrane. A transmembrane protein is a polytopic protein that spans an entire biological membrane. Transmembrane proteins aggregate and precipitate in water. They require detergents or nonpolar solvents for extraction, although some of them (beta-barrels) can be also extracted using denaturing agents.