The seven-transmembrane spanning topography of the Alzheimer disease-related presenilin proteins in the plasma membranes of cultured cells
The seven-transmembrane spanning topography of the Alzheimer disease-related presenilin proteins in the plasma membranes of cultured cells
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DOI：
10.1073/pnas.94.25.14025
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发表时间：
1997-12-09
影响因子：
11.1
通讯作者：
Singer, SJ
中科院分区：
文献类型：
--
作者：
Dewji, NN;Singer, SJ
为了确定多跨膜早老素蛋白PS-1和PS-2的膜地形，对这两种蛋白中的几个特定氨基酸序列产生抗肽抗体，在确定其特异性后，使用抗肽抗体对ps转染的活的培养的DAMI细胞进行免疫荧光标记，这些细胞对抗体不渗透，以及它们的固定和渗透对抗性。在这样的实验中，特异性染色完整活细胞的抗体必须标记在质膜外表面的PS蛋白的表位，而那些不染色活细胞但染色固定和渗透细胞的抗体必须标记面对膜细胞质侧的表位。所得结果与预测的七跨膜结构（如视紫红质和p -肾上腺素能受体）完全一致，而与预测的六或八跨膜结构完全不一致。
To ascertain the membrane topography of the multi-transmembrane spanning presenilin proteins PS-1 and PS-2, anti-peptide antibodies were raised to several specific amino acid sequences in the two proteins, and, after their specificity was ascertained, the anti-peptide antibodies were used in immunofluorescent labeling of live PS-transfected, cultured DAMI cells, which are impermeable to the antibodies, as well as of their fixed and permeabilized counterparts. In such experiments, antibodies that specifically stain the intact live cells must label epitopes of the PS proteins that are on the exterior face of the plasma membrane whereas those antibodies that do not stain the live cells but do stain the fixed and permeabilized cells must label epitopes that face the cytoplasmic side of the membrane. The results obtained were entirely in accord with the predictions of the seven-transmembrane spanning topography (like that of rhodopsin and the P-adrenergic receptor) and were totally inconsistent with the expectations for either the six-or eight-transmembrane topographies that have been proposed.