Division of Bioinformation, Department of Physiology, Hyogo College of Medicine, 1-1 Mukogawa-cho, Nishinomiya 663-8501, Japan.
Biochem J. 2013 Mar 1;450(2):303-9. doi: 10.1042/BJ20121348.
In yeast two-hybrid screening, protein 4.1N, a scaffolding protein, was identified as a binding partner of the α7 ACh (acetylcholine) receptor. For rat hippocampal slices, the linoleic acid derivative DCP-LA {8-[2-(2-pentyl-cyclopropylmethyl)-cyclopropyl]-octanoic acid} increased the association of the α7 ACh receptor with 4.1N, and the effect was inhibited by GF109203X, an inhibitor of PKC (protein kinase C), although DCP-LA did not induce PKC phosphorylation of 4.1N. For PC-12 cells, the presence of the α7 ACh receptor in the plasma membrane fraction was significantly suppressed by knocking down 4.1N. DCP-LA increased the presence of the α7 ACh receptor in the plasma membrane fraction, and the effect was still inhibited by knocking down 4.1N. In the monitoring of α7 ACh receptor mobilization, DCP-LA enhanced signal intensities for the α7 ACh receptor at the membrane surface in PC-12 cells, which was clearly prevented by knocking down 4.1N. Taken together, the results of the present study show that 4.1N interacts with the α7 ACh receptor and participates in the receptor tethering to the plasma membrane. The results also indicate that DCP-LA increases membrane surface localization of the α7 ACh receptor in a 4.1N-dependent manner under the control of PKC, but without phosphorylating 4.1N.
在酵母双杂交筛选中，支架蛋白 4.1N 被鉴定为α7 ACh（乙酰胆碱）受体的结合伴侣。对于大鼠海马切片，亚油酸衍生物 DCP-LA{8-[2-(2-戊基环丙基甲基）-环丙基]-辛酸}增加了α7 ACh 受体与 4.1N 的结合，该作用被 PKC（蛋白激酶 C）抑制剂 GF109203X 抑制，尽管 DCP-LA 没有诱导 4.1N 的 PKC 磷酸化。对于 PC-12 细胞，敲低 4.1N 显著抑制α7 ACh 受体在质膜部分的存在。DCP-LA 增加了α7 ACh 受体在质膜部分的存在，并且该作用仍然被敲低 4.1N 抑制。在α7 ACh 受体易位监测中，DCP-LA 增强了 PC-12 细胞中α7 ACh 受体在膜表面的信号强度，而敲低 4.1N 则明显阻止了这一作用。综上所述，本研究结果表明 4.1N 与α7 ACh 受体相互作用并参与受体与质膜的连接。结果还表明，在 PKC 的控制下，DCP-LA 以 4.1N 依赖的方式增加α7 ACh 受体在膜表面的定位，但不磷酸化 4.1N。
