title: Interaction of Golgin-84 with the COG complex mediates the intra-Golgi retrograde transport.
abstract: The coiled-coil Golgi membrane protein golgin-84 functions as a tethering factor for coat protein I (COPI) vesicles. Protein interaction analyses have revealed that golgin-84 interacts with another tether, the conserved oligomeric Golgi (COG) complex, through its subunit Cog7. Therefore, we explored the function of golgin-84 as the tether for COPI vesicles of intra-Golgi retrograde traffic. First, glycosylic maturation of both plasma membrane (CD44) and lysosomal (lamp1) glycoproteins was distorted in golgin-84 knockdown (KD) cells. The depletion of golgin-84 caused fragmentation of the Golgi with the mislocalization of Golgi resident proteins, resulting in the accumulation of vesicles carrying intra-Golgi soluble N-ethylmaleimide-sensitive factor attachment protein receptors (SNAREs) and cis-Golgi membrane protein GPP130. Similar observations were obtained by diminution of the COG complex, suggesting a strong correlation between the two tethers. Indeed, COG complex-dependent (CCD) vesicles that accumulate in Cog3 or Cog7 KD cells carried golgin-84. Surprisingly, the interaction between golgin-84 and another candidate tethering partner CASP (CDP/cut alternatively spliced product) decreased in Cog3 KD cells. These results indicate that golgin-84 on COPI vesicles interact with the COG complex before SNARE assembly, suggesting that the interaction of golgin-84 with COG plays an important role in the tethering process of intra-Golgi retrograde vesicle traffic.
authors.affiliation: Division of Oral Biochemistry, Niigata University Graduate School of Medical and Dental Sciences, Chuo-ku, Niigata 951-8514, Japan.
authors.forename: Miwa
authors.initials: M
authors.lastname: Sohda
authors.forename: Yoshio
authors.initials: Y
authors.lastname: Misumi
authors.forename: Akitsugu
authors.initials: A
authors.lastname: Yamamoto
authors.forename: Nobuhiro
authors.initials: N
authors.lastname: Nakamura
authors.forename: Shigenori
authors.initials: S
authors.lastname: Ogata
authors.forename: Shotaro
authors.initials: S
authors.lastname: Sakisaka
authors.forename: Shinichi
authors.initials: S
authors.lastname: Hirose
authors.forename: Yukio
authors.initials: Y
authors.lastname: Ikehara
authors.forename: Kimimitsu
authors.initials: K
authors.lastname: Oda
mesh_terms: D033942:Adaptor Proteins, Vesicular Transport / Q000378:metabolism; D001692:Biological Transport; D002460:Cell Line; D006056:Golgi Apparatus / Q000378:metabolism*; D000077614:Golgi Matrix Proteins; D006801:Humans; D018960:Hyaluronan Receptors; D051907:Lysosomal Membrane Proteins / Q000378:metabolism; D008565:Membrane Proteins / Q000378:metabolism*; D011485:Protein Binding; D050600:SNARE Proteins / Q000378:metabolism; D033921:Vesicular Transport Proteins / Q000378:metabolism; D052118:Lysosomal-Associated Membrane Protein 1
chemical_list: D033942:Adaptor Proteins, Vesicular Transport; D000077614:Golgi Matrix Proteins; D018960:Hyaluronan Receptors; D051907:Lysosomal Membrane Proteins; D008565:Membrane Proteins; D050600:SNARE Proteins; D033921:Vesicular Transport Proteins; C497483:CD44 protein, human; C498528:COG3 protein, human; C512294:COG7 protein, human; C060042:GOLGA5 protein, human; C489116:LAMP1 protein, human; D052118:Lysosomal-Associated Membrane Protein 1