|CD98||SLC3A2 (solute carrier family 3, activator of dibasic and neutral amino acid transport, member 2)), 4F2, FRP-1|
|Molecule Type||Antigen Expression||Molecular Weight|
Min / Max
|Non-lineage Restricted Molecule|
Type 2 glycoprotein
|80 / 80|
|CD98 is expressed on activated and transformed cells, but not on hematopoietic specific cells and is expressed at lower levels on quiescent cells. CD98 is expressed at high levels on monocytes and on proliferating cells particularly on neoplastic cells, but at very low levels on peripheral blood T and B cells, splenocytes, NK cells and granulocytes. Con A and alloantigen-activated lymphocytes and activated NK cells express high levels of this antigen. It is also expressed on some hematopoietic cells. All human cell lines studied express CD98. Studies in mouse show CD98 is expressed at the beginning of hematopoiesis.|
|MOLECULAR FAMILY NAME: Belongs to the SLA3A transporter family.|
CD98 is a disulfide-linked heterodimeric single-pass type-2 529 aa glycoprotein. It contains a signal sequence, an extracellular domain, a transmembrane domain and a cytoplasic domain. The glycoprotein forms disulphide bonds with at least 6 different light chains that act as amino acid tranporters. The transmembrane domain and in particular the N-terminal 5 aa of this domain are required for interaction with β1 integrins. CD98 exists as a glycosylated heavy chain of a heterodimer covalently bound through disulfide bonds to one of several possible light chains.
POST-TRANSCRIPTIONAL MODIFICATION: No information.
CD98 has a glycosylated heavy chain and a non-glycosylated light chain.
|LIGANDS AND MOLECULES ASSOCIATED WITH CD98|
CD98 binds with β1 integrins, CD29, CD147, tropomyosin and actin.
|CD98 functions in cell activation and aggregation and as a chaperone for amino acid transporters closely associated with actin. CD98 is implicated in the regulations of cell fusion and β1 integrin adhesive functions either directly or indirectly with β integrins. The interaction of CD98, basolateral amino acid transporters, and β1 integrins alters diverse cellular functions in polarized renal epithelial cells including amino acid transport, cell adhesion, migration and branching morphogenesis. CD98 antibodies inhibit lectin-induced T cell proliferation but not the mixed lymphocyte reaction, antibody-dependent cellular cytotoxicity or T-cell mediated cytotoxicity. Expression of CD98 can be upregulated in the presence of IFN-γ. |
BIOCHEMICAL ACTIVITY: No information.
DISEASE RELEVANCE AND FUNCTION OF INTACT ANIMAL
Overexpression of CD98 was demonstrated to result in growth in fibroblasts and activation of certain integrin regulating signaling pathways which promote tumorigensis.
PROTEINS AND DNA ELEMENTS WHICH REGULATE TRANSCRIPTION OF CD98: No information.
SUBSTRATES: No information.
ENZYMES WHICH MODIFY CD98: No information.
Database accession numbers
Revised June 25, 2008