GRIP domain-mediated targeting of two new coiled-coil proteins, GCC88 and GCC185, to subcompartments of the trans-Golgi network
GRIP domain-mediated targeting of two new coiled-coil proteins, GCC88 and GCC185, to subcompartments of the trans-Golgi network
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DOI：
10.1074/jbc.m210387200
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发表时间：
2003-02-07
影响因子：
4.8
通讯作者：
Gleeson, PA
中科院分区：
文献类型：
--
作者：
Luke, MR;Kjer-Nielsen, L;Gleeson, PA
GRIP结构域是在卷曲型外周高尔基蛋白家族中发现的一个靶向序列。先前我们证明了p230/golgin245的GRIP结构域被特异性募集到陷阱-高尔基网络（TGN）的管泡结构中。在这里，我们鉴定了两个具有功能性GRIP结构域的新型高尔基蛋白，命名为GCC88和GCC185。GCC88 cDNA编码一个88 kDa的蛋白，GCC185 cDNA编码一个185 kDa的蛋白。这两种分子都是brefeldin a敏感的外周膜蛋白，预计在C端具有广泛的具有GRIP结构域的卷曲卷曲区域。通过免疫荧光和免疫电镜观察，GCC88和GCC185以及GRIP蛋白golgin97均定位于Hela细胞的TGN。全长GCC88的过表达导致形成从陷阱-高尔基体延伸的大型电子密集结构。这些新结构包含GCC88和TGN标记syntaxin 6和TGN38的共同染色，但不包含alpha2,6-唾液基转移酶，β - cop或顺式高尔基GM130。这些异常结构的形成需要GCC88的n端结构域。TGN38在TGN和质膜之间循环，被运输进出GCC88修饰的结构。这些数据介绍了两个新的GRIP结构域蛋白，并暗示GCC88在参与膜运输的特定TGN亚室的组织中的作用。
The GRIP domain is a targeting sequence found in a family of coiled-coil peripheral Golgi proteins. Previously we demonstrated that the GRIP domain of p230/golgin245 is specifically recruited to tubulovesicular structures of the traps-Golgi network (TGN). Here we have characterized two novel Golgi proteins with functional GRIP domains, designated GCC88 and GCC185. GCC88 cDNA encodes a protein of 88 kDa, and GCC185 cDNA encodes a protein of 185 kDa. Both molecules are brefeldin A-sensitive peripheral membrane proteins and are predicted to have extensive coiled-coil regions with the GRIP domain at the C terminus. By immunofluorescence and immunoelectron microscopy GCC88 and GCC185, and the GRIP protein golgin97, are all localized to the TGN of Hela cells. Overexpression of full-length GCC88 leads to the formation of large electron dense structures that extend from the traps-Golgi. These de novo structures contain GCC88 and co-stain for the TGN markers syntaxin 6 and TGN38 but not for alpha2,6-sialyltransferase, beta-COP, or cis-Golgi GM130. The formation of these abnormal structures requires the N-terminal domain of GCC88. TGN38, which recycles between the TGN and plasma membrane, was transported into and out of the GCC88 decorated structures. These data introduce two new GRIP domain proteins and implicate a role for GCC88 in the organization of a specific TGN subcompartment involved with membrane transport.