CD98: Proteins and Enzymes

CD98, also known as 4F2, is a widely expressed disulfide-linked heterodimer in the solute transporter family. It consists of an 85 kDa glycosylated type II transmembrane heavy chain and a 40-50 kDa non-glycosylated light chain with 12 transmembrane segments. The heavy chain (SLC3A2) pairs with one of several light chains (SLC7A5, 6, 7, 8, 10, or 11) and is required for the cell surface expression and amino acid transport function of the light chains. CD98 also mediates integrin signaling, T cell costimulation, B cell proliferation, and viral fusion with cell membranes. Within the extracellular region, human CD98 heavy chain shares 73% and 71% aa sequence identity with mouse and rat CD98 heavy chain, respectively.