Culvenor J G, Maher F, Evin G, Malchiodi-Albedi F, Cappai R, Underwood J R, Davis J B, Karran E H, Roberts G W, Beyreuther K, Masters C L
Department of Pathology, The University of Melbourne, Parkville, Victoria, Australia.
J Neurosci Res. 1997 Sep 15;49(6):719-31. doi: 10.1002/(SICI)1097-4547(19970915)49:6<719::AID-JNR6>3.0.CO;2-A.
The recently identified Alzheimer's disease-associated presenilin 1 and 2 (PS1 and PS2) genes encode two homologous multi membrane-spanning proteins. Rabbit antibodies to the N-terminal domain of PS1 detected PS1 in human neuroblastoma SH-SY5Y wild type and PS1 transfectants (SY5Y-PS1) as well as in mouse P19, in CHO-K1 and CHO-APP770 transfected cells, in rat cerebellar granule and hippocampal neurons, and astrocytes. Immunoblotting detected full-length protein of 50 kDa, and a major presumptive cleavage product of 30 kDa. The immunofluorescence pattern resembled labeling of the endoplasmic reticulum-Golgi intermediate compartment (ERGIC) marker protein ERGIC-53. PS1 distribution showed slight condensation after brefeldin A and more marked condensation after incubation of cells at 16 degrees C, characteristic of the ERGIC compartment. Double labeling showed colocalization of ERGIC-53 with PS1 in the SY5Y-PS1 cells. PS1 labeling of SY5Y-PS1 and P19 cells showed overlap of the cis-Golgi marker p210 and colocalization with p210 after brefeldin A which causes redistribution of p210 to the ERGIC. Expression of PS1 did not change in level or cellular distribution during development of neurons in culture. Double labeling for the amyloid precursor protein (APP) and PS1 on SY5Y-PS1 cells and CHO-APP770 cells showed some overlap under control conditions. These results indicate that PS1 is a resident protein of the ERGIC and could be involved in trafficking of proteins, including APP, between the ER and Golgi compartments.
最近发现的与阿尔茨海默病相关的早老素1和2（PS1和PS2）基因编码两种同源的多跨膜蛋白。针对PS1 N端结构域的兔抗体在人神经母细胞瘤SH-SY5Y野生型和PS1转染细胞（SY5Y-PS1）中检测到PS1，也在小鼠P19、CHO-K1和转染了CHO-APP770的细胞、大鼠小脑颗粒神经元、海马神经元以及星形胶质细胞中检测到PS1。免疫印迹检测到50 kDa的全长蛋白以及一个主要的推测性裂解产物30 kDa。免疫荧光模式类似于内质网-高尔基体中间区室（ERGIC）标记蛋白ERGIC-53的标记。PS1分布在布雷菲德菌素A处理后显示出轻微浓缩，在16℃孵育细胞后浓缩更明显，这是ERGIC区室的特征。双重标记显示在SY5Y-PS1细胞中ERGIC-53与PS1共定位。SY5Y-PS1和P19细胞的PS1标记显示顺式高尔基体标记p210有重叠，在布雷菲德菌素A处理后p210重新分布到ERGIC时与p210共定位。在培养的神经元发育过程中，PS1的表达水平和细胞分布没有变化。对SY5Y-PS1细胞和CHO-APP770细胞上的淀粉样前体蛋白（APP）和PS1进行双重标记，在对照条件下显示出一些重叠。这些结果表明PS1是ERGIC的驻留蛋白，可能参与包括APP在内的蛋白质在ER和高尔基体区室之间的运输。
