Vascular Endothelium - Tissue Functioning and Remodeling in the Circulatory and Ventilatory Systems - page 514

Table 9.20. Transmembrane transport of cationic amino acids. Amino acid transporters are made
of a light and a heavy chain.

SLC alias Transport system alias

L transport system

SLC7a5 LAT1 (light chain)

SLC7a8 LAT2

SLC3a2 4F2HC (heavy chain)
y + transport system
SLC7a1 CAT1 (light chain)

SLC7a2 CAT2

SLC7a3 CAT3

SLC7a4 CAT4

SLC3a2 4F2HC (heavy chain)

y + L transport system
SLC7a7

y + LAT1 (light chain)

y + LAT2 SLC7a6

SLC3a2 4F2HC (heavy chain)
b 0 + and B 0 + transport system
SLC7a9 BAT1 (light chain)

SLC3a1 rBAT (heavy chain)
x c transport system
SLC7a11

xCT (light chain)

SLC3a2 4F2HC (heavy chain)

asc transport system
SLC7a10 Asc1 (light chain)

SLC3a2 4F2HC (heavy chain)

transported through the cellular membrane by 4 transport systems (y + ,y + L, b 0 + ,
and B 0 + ;Table 9.20 ). Both y

+ and y + -like transport systems are inhibited by

arginine and lysine.
The Na + -independent L transport system carries large neutral amino acids with
branched or aromatic side chains, such as leucine, isoleucine, valine, phenylalanine,
tyrosine, and tryptophan. L-type (large neutral) amino acid transporters include
LAT1, or SLC7a5 carrier, LAT2, or SLC7a8 carrier.
The y + transport system is insensitive to neutral amino acids (NAA) and does not
depend on pH. It mediates the bidirectional CAA transport. The y + transfer system
is based on cationic amino acid (CAA) transporter (CAT) that carries

L arginine,