This gene encodes a multi-pass transmembrane protein that is a functional component of the gamma-secretase complex, which also contains presenilin and nicastrin. This protein represents a stabilizing cofactor for the presenilin holoprotein in the complex. The gamma-secretase complex catalyzes the cleavage of integral proteins such as notch receptors and beta-amyloid precursor protein. [provided by RefSeq, Sep 2011].