SLC3A2

4F2 cell-surface antigen heavy chain is a protein that in humans is encoded by the SLC3A2 (solute carrier family 3 member 2) gene.

SLC3A2 comprises the light subunit of the large neutral amino acid transporter (LAT1) that is also known as CD98 (cluster of differentiation 98).

Function

SLC3A2 is a member of the solute carrier family and encodes a cell surface, transmembrane protein with an alpha-amylase domain. The protein exists as the heavy chain of a heterodimer, covalently bound through di-sulfide bonds to one of several possible light chains. It associates with integrins and mediates integrin-dependent signaling related to normal cell growth and tumorigenesis. Alternate transcriptional splice variants, encoding different isoforms, have been characterized.

LAT1 is a heterodimeric membrane transport protein that preferentially transports neutral branched (valine, leucine, isoleucine) and aromatic (tryptophan, tyrosine) amino acids. LAT is highly expressed in brain capillaries (which form the blood brain barrier) relative to other tissues.