Reconstitution of functional muscarinic receptors by co‐expression of amino‐ and carboxyl‐terminal receptor fragments

FEBS Letters

Wess, Jürgen¹  Vogel, Zvi¹  Maggio, Roberto¹ 

[1] National Institute of Neurological Disorders and Stroke, Laboratory of Molecular Biology, Bethesda, MD 20892, USA

关键词: G protein-coupled receptor;    Muscarinic receptor;    Phosphatidyl inositol hydrolysis;    Protein folding;    Truncated receptor;    NMS;    N-methylscopolamine chloride;    G protein;    guanine nucleotide-binding protein;    i3;    third cytoplasmic loop;    PI;    phosphatidyl inositol;    TM I-VII;    the seven transmembrane domains of G protein-coupled receptors;    IP1;    inositol monophosphate;    4-DAMP;    4-diphenylacetoxy-N-methylpiperidine methiodide;   

DOI  :  10.1016/0014-5793(93)80066-4

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Truncated m2 and m3 muscarinic receptors (referred to as m2- and m3-trunc), containing transmembrane domains I-V and the N-terminal portion of the third cytoplasmic loop, were co-expressed in COS-7 cells with the corresponding C-tenninal receptor fragments (referred to as m2- and m3-tail; containing transmembrane domains VI and VII). Expression of any of these four polypeptides alone did not result in any detectable [³H]N-methylscopolamine ([³H]NMS) binding activity. However, specific [³H]NMS binding sites were observed after co-expression of m2-trunc with m2-tail and m3-trunc with m3-tail. These sites displayed ligand binding properties similar to those of the two wild-type receptors. The ‘reconstituted’ m3-trunc/m3-tail receptor was also able to stimulate agonist-dependent phosphatidyl inositol hydrolysis in a fashion similar to the wild-type m3 receptor, whereas all other polypeptide combinations were inactive. These data suggest that muscarinic receptors are assembled in a fashion analogous to two-subunit receptors.

【 授权许可】

Unknown