Membrane topology distinguishes a subfamily of the ATP‐binding cassette (ABC) transporters

FEBS Letters

Bakos, Éva²  Tusnády, Gábor E²  Váradi, András²  Sarkadi, Balázs¹ 

[1] National Institute of Haematology and Immunology, and Membrane Research Group of the Hungarian Academy of Sciences, Daróczi u. 24, H-1113 Budapest, Hungary;Institute of Enzymology, Biological Research Center, Hungarian Academy of Sciences, H-1113 Budapest, Hungary

关键词: Membrane topology;    ABC transporter;    MRP;    SUR;    YCF1;    cMOAT;   

DOI  :  10.1016/S0014-5793(96)01478-0

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

A group of ATP-binding cassette (ABC) transporters, including the yeast cadmium transporter (YCF1), the mammalian multidrug resistance-associated protein (MRP), the multispecific organic anion transporter and its congener (MOAT and EBCR), as well as the sulfonylurea receptor (SUR), group into a subfamily by sequence comparison. We suggest that these MRP-related proteins are also characterized by a special, common membrane topology pattern. The most studied ABC transporters, the cystic fibrosis transmembrane conductance regulator (CFTR) and the multidrug resistance (MDR) proteins, were shown to contain a tandem repeat of six transmembrane helices, each set followed by an ATP-binding domain. According to the present study, in contrast to various membrane topology predictions proposed for the different MRP-related proteins, they all seem to have a CFTR/MDR-like core structure, and an additional, large, N-terminal hydrophobic region. This latter domain is predicted to contain 4–6 (most probably 5) transmembrane helices, and is occasionally glycosylated on the cell surface. Since all the MRP-related transporters were shown to interact with anionic compounds, the N-terminal membrane-bound domain may have a key role in these interactions.

【 授权许可】

Unknown