TY - JOUR
T1 - Differential influence of the 4F2 heavy chain and the protein related to b0,+ amino acid transport on substrate affinity of the heteromeric b0,+ amino acid transporter
AU - Rajan, D. Prasanna
AU - Huang, Wei
AU - Kekuda, Ramesh
AU - George, Ronald L.
AU - Wang, Jian
AU - Conway, Simon J.
AU - Devoe, Lawrence D
AU - Leibach, Frederick H.
AU - Prasad, Puttur D
AU - Ganapathy, Vadivel
PY - 2000/5/12
Y1 - 2000/5/12
N2 - We provide evidence here that b0,+ amino acid transporter (b0,+ AT) interacts with 4F2 heavy chain (4F2hc) as well as with the protein related to b amino acid transporter (rBAT) to constitute functionally competent b0,+-like amino acid transport systems. This evidence has been obtained by co-expression of b0,+ AT and 4F2hc or b0,+AT and rBAT in human retinal pigment epithelial cells and in COS-1 cells. The ability to interact with 4F2hc and rBAT is demonstrable with mouse b0,+AT as well as with human b0,+AT. Even though both the 4F2hc.b0,+AT complex and the rBAT·b0,+ AT complex exhibit substrate specificity that is characteristic of system b0,+, these two complexes differ significantly in substrate affinity. The 4F2hc·b0,+AT complex has higher substrate affinity than the rBAT·b0,+AT complex. In situ hybridization studies demonstrate that the regional distribution pattern of mRNA in the kidney is identical for b0,+ AT and 4F2hc. The pattern of rBAT mRNA expression is different from that of b0,+AT mRNA and 4F2hc mRNA, but there are regions in the kidney where b0,+AT mRNA expression overlaps with rBAT mRNA expression as well as with 4F2hc mRNA expression.
AB - We provide evidence here that b0,+ amino acid transporter (b0,+ AT) interacts with 4F2 heavy chain (4F2hc) as well as with the protein related to b amino acid transporter (rBAT) to constitute functionally competent b0,+-like amino acid transport systems. This evidence has been obtained by co-expression of b0,+ AT and 4F2hc or b0,+AT and rBAT in human retinal pigment epithelial cells and in COS-1 cells. The ability to interact with 4F2hc and rBAT is demonstrable with mouse b0,+AT as well as with human b0,+AT. Even though both the 4F2hc.b0,+AT complex and the rBAT·b0,+ AT complex exhibit substrate specificity that is characteristic of system b0,+, these two complexes differ significantly in substrate affinity. The 4F2hc·b0,+AT complex has higher substrate affinity than the rBAT·b0,+AT complex. In situ hybridization studies demonstrate that the regional distribution pattern of mRNA in the kidney is identical for b0,+ AT and 4F2hc. The pattern of rBAT mRNA expression is different from that of b0,+AT mRNA and 4F2hc mRNA, but there are regions in the kidney where b0,+AT mRNA expression overlaps with rBAT mRNA expression as well as with 4F2hc mRNA expression.
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U2 - 10.1074/jbc.275.19.14331
DO - 10.1074/jbc.275.19.14331
M3 - Article
C2 - 10799513
AN - SCOPUS:0034640396
SN - 0021-9258
VL - 275
SP - 14331
EP - 14335
JO - Journal of Biological Chemistry
JF - Journal of Biological Chemistry
IS - 19
ER -