System L-amino acid transporters are differently expressed in rat astrocyte and C6 glioma cells.
The system L-amino acid transporter is a major nutrient transport system that is responsible for Na+-independent transport of neutral amino acids including several essential amino acids. We have compared and examined the expressions and functions of the system L-amino acid transporters in both rat astrocyte cultures and C6 glioma cells. The rat astrocyte cultures expressed the l-type amino acid transporter 2 (LAT2) with its subunit 4F2hc, whereas the l-type amino acid transporter 1 (LAT1) was not expressed in these cells. The C6 glioma cells expressed LAT1 but not LAT2 with 4F2hc. The [14C]l-leucine uptakes by the rat astrocyte cultures and C6 glioma cells were Na+-independent and were completely inhibited by the system l selective inhibitor, BCH. These results suggest that the transport of neutral amino acids including several essential amino acids into rat astrocyte cultures and C6 glioma cells are for the most part mediated by LAT2 and LAT1, respectively. Therefore, the rat astrocyte cultures and C6 glioma cells are excellent tools for examining the properties of LAT2 and LAT1, respectively. Moreover, the specific inhibition of LAT1 in cancer cells might be a new rationale for anti-cancer therapy.
Kim
Do Kyung
DK
Department of Oral Physiology, Chosun University College of Dentistry, 375 Seosuk-dong, Dong-gu, Gwangju, 501-759, South Korea. kdk@chosun.ac.kr
Kim
In Jin
IJ
Hwang
Shinae
S
Kook
Ji Hyun
JH
Lee
Min-Cheol
MC
Shin
Boo Ahn
BA
Bae
Choon Sang
CS
Yoon
Jung Hoon
JH
Ahn
Sang Gun
SG
Kim
Soo A
SA
Kanai
Yoshikatsu
Y
Endou
Hitoshi
H
Kim
Jong-Keun
JK
D027182:Amino Acid Transport System y+ / Q000187:drug effects / Q000378:metabolism*; D000598:Amino Acids, Cyclic / Q000494:pharmacology; D021542:Amino Acids, Neutral / Q000378:metabolism; D000818:Animals; D000831:Animals, Newborn; D001253:Astrocytes / Q000378:metabolism*; D001693:Biological Transport, Active / Q000502:physiology; D001921:Brain / Q000378:metabolism* / Q000503:physiopathology; D001932:Brain Neoplasms / Q000188:drug therapy / Q000378:metabolism*; D002250:Carbon Radioisotopes / Q000378:metabolism; D045744:Cell Line, Tumor; D002478:Cells, Cultured; D027282:Fusion Regulatory Protein 1, Heavy Chain / Q000378:metabolism; D027301:Fusion Regulatory Protein 1, Light Chains / Q000187:drug effects / Q000378:metabolism*; D005910:Glioma / Q000188:drug therapy / Q000378:metabolism*; D027283:Large Neutral Amino Acid-Transporter 1 / Q000187:drug effects / Q000378:metabolism*; D007930:Leucine / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar
D027182:Amino Acid Transport System y+; D000598:Amino Acids, Cyclic; D021542:Amino Acids, Neutral; D002250:Carbon Radioisotopes; D027282:Fusion Regulatory Protein 1, Heavy Chain; D027301:Fusion Regulatory Protein 1, Light Chains; D027283:Large Neutral Amino Acid-Transporter 1; C486582:Slc7a8 protein, rat; C006504:2-aminobicyclo(2,2,1)heptane-2-carboxylic acid; D007930:Leucine