HLC-3 is a 796 amino acid protein that is widely expressed in many tissues, including kidney, lung, liver, brain and skeletal and cardiac muscle. SLC4A1AP is a multidomain protein that localizes to the nucleus where it may play a role in signaling. SLC4A1AP was previously thought to act as an adaptor protein or chaperone involved in targeting kAE1 to the plasma membrane. However, recent studies suggest SLC4A1AP does not interact with kAE1. The gene encoding SLC4A1AP maps to chromosome 2, which consists of 237 million bases and makes up approximately 8% of the human genome. A number of genetic diseases are linked to genes on chromosome 2, including Harlequin icthyosis, sitosterolemia and Alstr鰉 syndrome.