Component of several heterodimeric complexes involved in amino acid transport (PubMed:
11557028, PubMed:
9829974, PubMed:
9751058, PubMed:
10391915, PubMed:
10574970, PubMed:
11311135, PubMed:
30341327). The precise substrate specificity depends on the other subunit in the heterodimer (PubMed:
9829974, PubMed:
9751058, PubMed:
10391915, PubMed:
10574970, PubMed:
30867591, PubMed:
10903140). The complexes function as amino acid exchangers (PubMed:
11557028, PubMed:
10903140, PubMed:
12117417, PubMed:
12225859, PubMed:
30867591). The homodimer functions as sodium-independent, high-affinity transporter that mediates uptake of large neutral amino acids such as phenylalanine, tyrosine, L-DOPA, leucine, histidine, methionine and tryptophan (PubMed:
9751058, PubMed:
11557028, PubMed:
11311135, PubMed:
11564694, PubMed:
12117417, PubMed:
12225859, PubMed:
25998567, PubMed:
30867591). The heterodimer formed by SLC3A2 and SLC7A6 or SLC3A2 and SLC7A7 mediates the uptake of dibasic amino acids (PubMed:
9829974, PubMed:
10903140). The heterodimer with SLC7A5/LAT1 mediates the transport of thyroid hormones triiodothyronine (T3) and thyroxine (T4) across the cell membrane (PubMed:
11564694, PubMed:
12225859). The heterodimer with SLC7A5/LAT1 is involved in the uptake of toxic methylmercury (MeHg) when administered as the L-cysteine or D,L- homocysteine complexes (PubMed:
12117417). The heterodimer with SLC7A5/LAT1 is involved in the uptake of leucine (PubMed:
25998567, PubMed:
30341327). When associated with LAPTM4B, the heterodimer with SLC7A5/LAT1 is recruited to lysosomes to promote leucine uptake into these organelles, and thereby mediates mTORC1 activation (PubMed:
25998567). The heterodimer with SLC7A5/LAT1 may play a role in the transport of L-DOPA across the blood-brain barrier (By similarity). The heterodimer formed by SLC3A2 and SLC7A5/LAT1 or SLC3A2 and SLC7A8/LAT2 is involved in the cellular activity of small molecular weight nitrosothiols, via the stereoselective transport of L- nitrosocysteine (L-CNSO) across the transmembrane (PubMed:
15769744). Together with ICAM1, regulates the transport activity of SLC7A8/LAT2 in polarized intestinal cells by generating and delivering intracellular signals (PubMed:
12716892). Required for targeting of SLC7A5/LAT1 and SLC7A8/LAT2 to the plasma membrane and for channel activity (PubMed:
9751058, PubMed:
11311135, PubMed:
30867591). Plays a role in nitric oxide synthesis in human umbilical vein endothelial cells (HUVECs) via transport of L-arginine (PubMed:
14603368). May mediate blood-to-retina L-leucine transport across the inner blood-retinal barrier (By similarity).
