Glutamine transport in C6 glioma cells shows ASCT2 system characteristics

被引：37

作者：

Dolinska, M

Dybel, A

Zablocka, B

Albrecht, J

机构：

[1] Polish Acad Sci, Dept Neurotoxicol, Med Res Ctr, PL-02106 Warsaw, Poland

[2] Polish Acad Sci, Mol Biol Lab, Med Res Ctr, PL-02106 Warsaw, Poland

来源：

NEUROCHEMISTRY INTERNATIONAL | 2003年 / 43卷 / 4-5期

关键词：

glutamine uptake; threonine uptake; glutamate uptake; C6; cells; system ASCT2; sodium-dependence; chloride-dependence;

D O I：

10.1016/S0197-0186(03)00040-8

中图分类号：

Q5 [生物化学]; Q7 [分子生物学];

学科分类号：

071010 ; 081704 ;

摘要：

Previous studies from this laboratory have shown that glutamine (Gln) uptake in a rat astrocytoma-derived C6 cell line shows characteristics similar with the uptake of a model ASC system substrate, threonine, whose pH-dependence and partial tolerance of Li+ substitution for Na+ resemble the ASCT2 variant of the system. In support of the previous findings, RT-PCR analysis revealed that C6 cells strongly express ASCT2 mRNA, but not at all GlnT mRNA or NAT2 mRNA, the A and N system variants specifically engaged in Gln transport in normal CNS. Other features of Gln transport in C6 cells indicating the involvement of ASCT2 system included its resistance to ouabain and stimulation of Gln efflux from the cells in the presence of excess Gln or cysteine (Cys), demonstrating that the system operates in the exchange mode. Replacement of NaCl in the incubation medium with isoosmotic sucrose did neither significantly affect the kinetics, nor any other major characteristics of Gln or Thr transport, including its pH-dependence, inhibition by ASCT system substrates or resistance to the model system A substrate-N-methylaniino-isobutyric acid (MeAiB). (C) 2003 Elsevier Science Ltd. All rights reserved.

引用

页码：501 / 507

页数：7

共 42 条

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