The discrepancy between presenilin subcellular localization and gamma-secretase processing of amyloid precursor protein.
The discrepancy between presenilin subcellular localization and gamma-secretase processing of amyloid precursor protein.
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DOI：
10.1083/jcb.200104045
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发表时间：
2001-08-20
期刊：
影响因子：
--
通讯作者：
Annaert W
中科院分区：
文献类型：
--
作者：
Cupers P;Bentahir M;Craessaerts K;Orlans I;Vanderstichele H;Saftig P;De Strooper B;Annaert W
我们研究了原代培养的神经元中PS1与γ-分泌酶加工淀粉样前体蛋白（APP）的关系。增加APP在细胞表面或向内体的量并不显著影响PS1依赖的γ-分泌酶切割，尽管在这些亚细胞区室中存在很少的PS1。相比之下，当γ-分泌酶的直接底物holo-APP或APP-C99通过双赖氨酸保留基序特异性保留在内质网（ER）中时，几乎没有观察到γ-分泌酶加工。然而，APP-C99-二赖氨酸（KK）与PS1共定位在ER中。相反，APP-C99不与PS1共定位，但被PS1依赖的γ-分泌酶有效加工。APP-C99存在于ER、中间室和高尔基体标记蛋白阴性的室中。我们的结论是，γ-分泌酶裂解APP-C99发生在一个专门的亚细胞区室，很少或没有PS1检测。这表明，APP-C99的γ-裂解需要至少一个位于ER下游的PS1以外的因子。与此一致，我们发现在布雷菲德菌素A处理后，APP-C99-KK在γ40和γ42位点的细胞内γ-分泌酶加工可以部分恢复。我们的数据证实了“空间悖论”，并提出了几个问题，PS1是γ-分泌酶假说。
We investigated the relationship between PS1 and γ-secretase processing of amyloid precursor protein (APP) in primary cultures of neurons. Increasing the amount of APP at the cell surface or towards endosomes did not significantly affect PS1-dependent γ-secretase cleavage, although little PS1 is present in those subcellular compartments. In contrast, almost no γ-secretase processing was observed when holo-APP or APP-C99, a direct substrate for γ-secretase, were specifically retained in the endoplasmic reticulum (ER) by a double lysine retention motif. Nevertheless, APP-C99-dilysine (KK) colocalized with PS1 in the ER. In contrast, APP-C99 did not colocalize with PS1, but was efficiently processed by PS1-dependent γ-secretase. APP-C99 resides in a compartment that is negative for ER, intermediate compartment, and Golgi marker proteins. We conclude that γ-secretase cleavage of APP-C99 occurs in a specialized subcellular compartment where little or no PS1 is detected. This suggests that at least one other factor than PS1, located downstream of the ER, is required for the γ-cleavage of APP-C99. In agreement, we found that intracellular γ-secretase processing of APP-C99-KK both at the γ40 and the γ42 site could be restored partially after brefeldin A treatment. Our data confirm the “spatial paradox” and raise several questions regarding the PS1 is γ-secretase hypothesis.
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影响因子：
4.8
作者：
Buxbaum, JD;Liu, KN;Black, RA
通讯作者：
Black, RA
影响因子：
21.3
作者：
Herreman, A;Serneels, L;De Strooper, B
通讯作者：
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DOI：
10.1073/pnas.96.7.3922
发表时间：
1999-03-30
影响因子：
11.1
作者：
Lammich, S;Kojro, E;Fahrenholz, F
通讯作者：
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影响因子：
82.9
作者：
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通讯作者：
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影响因子：
64.8
作者：
De Strooper, B;Saftig, P;Van Leuven, F
通讯作者：
Van Leuven, F