This domain is found at the N-terminus of solute carrier family 3 member 2 proteins (4F2 cell-surface antigen heavy chain).

1: Amino acid transport of y+L-type by heterodimers of 4F2hc/CD98 and members of the glycoprotein-associated amino acid transporter family. Pfeiffer R, Rossier G, Spindler B, Meier C, Kuhn L, Verrey F; EMBO J. 1999;18:49-57. PMID:9878049