gp74 a membrane glycoprotein of the cis-Golgi network that cycles through the endoplasmic reticulum and intermediate compartment.
gp74 a membrane glycoprotein of the cis-Golgi network that cycles through the endoplasmic reticulum and intermediate compartment.
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gp74顺式 - 高尔基网络的膜糖蛋白，该网络循环通过内质网和中间室。
DOI：
10.1083/jcb.124.5.649
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发表时间：
1994-03
影响因子：
7.8
通讯作者：
Sandoval, I V
中科院分区：
文献类型：
--
作者：
Alcalde, J;Egea, G;Sandoval, I V
一种单克隆抗体CC92（IgM），提出对富含高尔基体膜的大鼠肝脏的一部分，识别一种新的内H-抗性74-kD膜糖蛋白（gp74）。gp74的大部分被限制在顺式高尔基体网络（CGN）中。在高尔基体外，gp74存在于管泡状结构和ER灶中。在37 ℃孵育的细胞中，大部分gp74与中间室（IC）标记物p58分离。然而，在用细胞器扰动剂如低温、BFA和[AIF 4]处理的细胞中，这两种蛋白质的模式变得难以区分。这两种蛋白质在20 ℃时保留在高尔基复合体中，在15 ℃时保留在IC中。用BFA孵育细胞导致gp74重新定位到p58阳性IC元件。[AIF4]-诱导gp74从高尔基体重新分布到p58阳性囊泡，并且在用BFA处理的细胞中不阻碍gp74易位到IC元件。诺考达唑破坏微管导致gp74染色的高尔基体元件迅速消失，蛋白质重新分布成囊泡样结构。gp74对细胞扰动的反应与顺式/中间和反式高尔基体驻留蛋白的反应形成鲜明对比，这些蛋白的位置不受低温或[AIF 4]-的影响，在加入BFA后被易位到ER，并且在用诺考达唑处理的细胞中停留在缓慢崩解的高尔基体元件中。结果表明，gp74是一种巡回蛋白，大部分时间驻留在CGN中，并按照p58使用的途径循环通过ER/IC。
A monoclonal antibody CC92 (IgM), raised against a fraction of rat liver enriched in Golgi membranes, recognizes a novel Endo H-resistant 74-kD membrane glycoprotein (gp74). The bulk of gp74 is confined to the cis-Golgi network (CGN). Outside the Golgi gp74 is found in tubulovesicular structures and ER foci. In cells incubated at 37 degrees C the majority of gp74 is segregated from the intermediate compartment (IC) marker p58. However, in cells treated with organelle perturbants such as low temperature, BFA, and [AIF4]- the patterns of the two proteins become indistinguishable. Both proteins are retained in the Golgi complex at 20 degrees C and in the IC at 15 degrees C. Incubation of cells with BFA results in relocation of gp74 to p58 positive IC elements. [AIF4]- induces the redistribution of gp74 from the Golgi to p58-positive vesicles and does not retard the translocation of gp74 to IC elements in cells treated with BFA. Disruption of microtubules by nocodazol results in the rapid disappearance of the Golgi elements stained by gp74 and redistribution of the protein into vesicle-like structures. The responses of gp74 to cell perturbants are in sharp contrast with those of cis/middle and trans-Golgi resident proteins whose location is not affected by low temperatures or [AIF4]-, are translocated to the ER upon addition of BFA, and stay in slow disintegrating Golgi elements in cells treated with nocodazol. The results suggest that gp74 is an itinerant protein that resides most of the time in the CGN and cycles through the ER/IC following the pathway used by p58.