Protein: Large neutral amino acids transporter small subunit 1 (4F2 light chain) (4F2 LC) (4F2LC) (Integral membrane protein E16) (Protein TA1) (L-type amino acid transporter 1) (LAT-1) (Solute carrier family 7 member 5) (Q63016)
Organism: Rattus norvegicus (Rat)
Function: The heterodimer with SLC3A2 functions as sodium-independent, high-affinity transporter that mediates uptake of large neutral amino acids such as phenylalanine, tyrosine, L-DOPA, histidine, methionine, valine and alanine (By similarity). The heterodimer with SLC3A2 mediates the uptake of leucine, isoleucine and tryptophan. Functions as an amino acid exchanger (By similarity). May play a role in the transport of L-DOPA across the blood-brain barrier (By similarity). May act as the major transporter of tyrosine in fibroblasts (By similarity). May mediate blood-to-retina L-leucine transport across the inner blood-retinal barrier (Probable). Can mediate the transport of thyroid hormones diiodothyronine (T2), triiodothyronine (T3) and thyroxine (T4) across the cell membrane. When associated with LAPTM4B, the heterodimer formed by SLC3A2 and SLC7A5 is recruited to lysosomes to promote leucine uptake into these organelles, and thereby mediates mTORC1 activation. Involved in the uptake of toxic methylmercury (MeHg) when administered as the L-cysteine or D,L-homocysteine complexes. Involved in the cellular activity of small molecular weight nitrosothiols, via the stereoselective transport of L-nitrosocysteine (L-CNSO) across the membrane (By similarity).
Subcellular location: Apical cell membrane {ECO:0000250|UniProtKB:Q01650}; Multi-pass membrane protein {ECO:0000250|UniProtKB:Q01650}. Cell membrane {ECO:0000269|PubMed:11311135, ECO:0000269|PubMed:16027961}; Multi-pass membrane protein {ECO:0000250|UniProtKB:Q01650}. Lysosome membrane {ECO:0000250|UniProtKB:Q01650}; Multi-pass membrane protein {ECO:0000250|UniProtKB:Q01650}. Note=Located to the plasma membrane by SLC3A2/4F2hc. Localized to the apical membrane of placental syncytiotrophoblastic cells. Recruited to lysosomes by LAPTM4B (By similarity). Expressed in both luminal and abluminal membranes of brain capillary endothelial cells (PubMed:11095508). {ECO:0000250|UniProtKB:Q01650, ECO:0000269|PubMed:11095508}.
Interaction partners:
- Amino acid transporter heavy chain SLC3A2
- Neutral amino acid transporter B
- Amino acid transporter
- Amino acid transporter heavy chain SLC3A1
- LLGL scribble cell polarity complex component 2
- Sodium-coupled neutral amino acid symporter 1
- Large neutral amino acids transporter small subunit 4
- Solute carrier family 2, facilitated glucose transporter member 1
- Sodium-coupled neutral amino acid symporter 2
- Solute carrier family 43 member 1
Sequence:
MAVAGAKRRAVAAPATTAAEEERQAREKMLEARRGDGADPEGEGVTLQRNITLINGVAIIVGTIIGSGIFVTPTGVLKEAGSPGLSLVVWAVCGVFSIVGALCYAELGTTISKSGGDYAYMLEVYGSLPAFLKLWIELLIIRPSSQYIVALVFATYLLKPVFPTCPVPEEAAKLVACLCVLLLTAVNCYSVKAATRVQDAFAAAKLLALALIILLGFIQMGKDIGQGDASNLHQKLSFEGTNLDVGNIVLALYSGLFAYGGWNYLNFVTEEMINPYRNLPLAIIISLPIVTLVYVLTNLAYFTTLSTNQMLTSEAVAVDFGNYHLGVMSWIIPVFVGLSCFGSVNGSLFTSSRLFFVGSREGHLPSILSMIHPQLLTPVPSLVFTCVMTLMYAFSRDIFSIINFFSFFNWLCVALAIIGMMWLRFKKPELERPIKVNLALPVFFILACLFLIAVSFWKTPLECGIGFAIILSGLPVYFFGVWWKNKPKWILQVIFSVTVLCQKLMQVVPQET