Detailed Analysis of the Interaction of Yeast COG Complex

Cell Structure and Function

Vladimir V. Lupashin¹  Akihiko Nakano²  Midori Ishii³ 

[1] Department of Biological Sciences, Graduate School of Science, The University of Tokyo;Department of Physiology and Biophysics, University of Arkansas for Medical Sciences;Live Cell Super-Resolution Imaging Research Team, RIKEN Center for Advanced Photonics

关键词: The Golgi apparatus;    COG complex;    yeast;    membrane trafficking;    multi-subunit tethering complex;   

DOI  :  10.1247/csf.18014

学科分类：分子生物学，细胞生物学和基因

来源: Japan Society for Cell Biology

【 摘 要 】

The Golgi apparatus is a central station for protein trafficking in eukaryotic cells. A widely accepted model of protein transport within the Golgi apparatus is cisternal maturation. Each cisterna has specific resident proteins, which are thought to be maintained by COPI-mediated transport. However, the mechanisms underlying specific sorting of these Golgi-resident proteins remain elusive. To obtain a clue to understand the selective sorting of vesicles between the Golgi cisterenae, we investigated the molecular arrangements of the conserved oligomeric Golgi (COG) subunits in yeast cells. Mutations in COG subunits cause defects in Golgi trafficking and glycosylation of proteins and are causative of Congenital Disorders of Glycosylation (CDG) in humans. Interactions among COG subunits in cytosolic and membrane fractions were investigated by co-immunoprecipitation. Cytosolic COG subunits existed as octamers, whereas membrane-associated COG subunits formed a variety of subcomplexes. Relocation of individual COG subunits to mitochondria resulted in recruitment of only a limited number of other COG subunits to mitochondria. These results indicate that COG proteins function in the forms of a variety of subcomplexes and suggest that the COG complex does not comprise stable tethering without other interactors.

【 授权许可】

Unknown