Hydrophobic interactions mediate binding of the glycine receptor β-subunit to gephyrin
Hydrophobic interactions mediate binding of the glycine receptor β-subunit to gephyrin
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DOI：
10.1046/j.1471-4159.1999.0721323.x
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发表时间：
1999-03-01
影响因子：
4.7
通讯作者：
Betz, H
中科院分区：
文献类型：
--
作者：
Kneussel, M;Hermann, A;Betz, H
甘氨酸受体（GlyR）是由α-和β-亚基组成的配体门控氯离子通道蛋白。GlyR通过受体相关蛋白桥蛋白定位并锚定在突触后位点。我们实验室以前的工作已经确定了GlyR β亚基胞质环中桥蛋白结合的核心基序。在这里，我们本地化的氨基酸残基参与桥蛋白结合的定点诱变。在一种新的转染试验中，一种绿色荧光蛋白-桥蛋白结合基序融合蛋白被用来监测β-亚基与桥蛋白相互作用的氨基酸取代的后果。只有多个，但不是单一的，疏水侧链的替代废除了两种蛋白质之间的相互作用。我们的数据是一致的桥蛋白结合介导的疏水侧的一个不完美的两亲性螺旋。
Glycine receptors (GlyRs) are ligand-gated chloride channel proteins composed of alpha- and beta-subunits. GlyRs are located to and anchored at postsynaptic sites by the receptor-associated protein gephyrin. Previous work from our laboratory has identified a core motif for gephyrin binding in the cytoplasmic loop of the GlyR beta-subunit. Here, we localized amino acid residues implicated in gephyrin binding by site-directed mutagenesis. In a novel transfection assay, a green fluorescent protein-gephyrin binding motif fusion protein was used to monitor the consequences of amino acid substitutions for beta-subunit interaction with gephyrin. Only multiple, but not single, replacements of hydrophobic side chains abolished the interaction between the two proteins. Our data are consistent with gephyrin binding being mediated by the hydrophobic side of an imperfect amphipathic helix.