The fibril forming region of the beta-amyloid precursor differs from that of the amyloid A precursor in its interaction with lipids.
The fibril forming region of the beta-amyloid precursor differs from that of the amyloid A precursor in its interaction with lipids.
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β-淀粉样蛋白前体的原纤维形成区域与淀粉样蛋白A前体的原纤维形成区域的不同之处在于其与脂质的相互作用。
DOI：
10.1006/bbrc.1996.0332
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发表时间：
1996
影响因子：
3.1
通讯作者：
Sipe,JD
中科院分区：
文献类型：
--
作者：
Liang,JS;Fine,RE;Abraham,CR;Sipe,JD
由于淀粉样蛋白A （AA）前体，血清淀粉样蛋白A （apoSAA）已被证明在AA纤维形成区与胆固醇(C)结合，我们通过测量生理pH和离子强度下微滴孔结合的变化，研究了β-淀粉样蛋白前体蛋白（A - β pp）和β-淀粉样蛋白（Aβ）肽与C和磷脂酰胆碱（PC）的相互作用。虽然C或PC抑制Aβ pp结合的程度与C抑制apoSAA结合的程度相同，但C和PC对Aβ肽的结合没有任何影响，尽管Aβ1 - 40抗体确实阻止了结合。apoE3和apoE4能抑制125i - a β1 - 40和125i - a β pp的结合，apoSAA和牛血清白蛋白均不能抑制其结合。将bound125i - a - β pp部分释放到含有C、PC、apoE3、apoE4或a - β pp抗体的培养基中。我们的研究结果表明，在C和PC存在的情况下，Aβ pp而不是Aβ肽可以保留在溶液中，这表明这种与脂质相互作用的失败可能是Aβ原纤维比AA原纤维更不溶解的原因。
Since the amyloid A (AA) precursor, serum amyloid A (apoSAA), has been shown to bind cholesterol (C) in the AA fibril forming region, we investigated the interaction of the β-amyloid precursor protein (AβPP) and β-amyloid (Aβ) peptide with C and phosphatidyl choline (PC) by measuring changes in binding to microtiter wells at physiological pH and ionic strength. While either C or PC inhibited AβPP binding to the same extent that C inhibited apoSAA binding, neither C nor PC had any effect on binding of the Aβ peptide, although antibodies to Aβ1–40 did block binding. The binding of125I-Aβ1–40 and125I-AβPP was inhibited by apoE3 and apoE4, but not by either apoSAA or bovine serum albumin. Bound125I-AβPP was partially released into medium containing C, PC, apoE3, apoE4, or antibodies to AβPP. Our results indicate that AβPP but not Aβ peptide can be retained in solution in the presence of C and PC and suggest that this failure to interact with lipids may account for the greater insolubility of Aβ fibrils than AA fibrils.