Extralarge XLas (XXLas), a variant of stimulatory G protein alpha-subunit (Gsα), is a distinct, membrane-anchored GNAS product that can mimic Gsa - Aydin, C; Aytan, N; Mahon, M J; Tawfeek, H A; Kowall, N W; Dedeoglu, A; Bastepe, M (Endocrinology, 2009)