A novel Rab6-interacting domain defines a family of Golgi-targeted coiled-coil proteins

Curr Biol. 1999 Apr 8;9(7):381-4. doi: 10.1016/s0960-9822(99)80167-5.

Abstract

In recent years, a large number of coiled-coil proteins localised to the Golgi apparatus have been identified using antisera from human patients with a variety of autoimmune conditions [1]. Because of their common method of discovery and extensive regions of coiled-coil, they have been classified as a family of proteins, the golgins [1]. This family includes golgin-230/245/256, golgin-97, GM130/golgin-95, golgin-160/MEA-2/GCP170, giantin/macrogolgin and a related group of proteins - possibly splice variants - GCP372 and GCP364[2][3][4][5][6][7][8][9][10][11]. GM130 and giantin have been shown to function in the p115-mediated docking of vesicles with Golgi cisternae [12]. In this process, p115, another coiled-coil protein, is though to bind to giantin on vesicles and to GM130 on cisternae, thus acting as a tether holding the two together [12] [13]. Apart from giantin and GM130, none of the golgins has yet been assigned a function in the Golgi apparatus. In order to obtain clues as to the functions of the golgins, the targeting to the Golgi apparatus of two members of this family, golgin-230/245/256 and golgin-97, was investigated. Each of these proteins was shown to target to the Golgi apparatus through a carboxy-terminal domain containing a conserved tyrosine residue, which was critical for targeting. The domain preferentially bound to Rab6 on protein blots, and mutations that abolished Golgi targeting resulted in a loss of this interaction. Sequence analysis revealed that a family of coiled-coil proteins from mammals, worms and yeast contain this domain at their carboxyl termini. One of these proteins, yeast Imh1p, has previously been shown to have a tight genetic interaction with Rab6 [14]. On the basis of these data, it is proposed that this family of coiled-coil proteins functions in Rab6-regulated membrane-tethering events.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Autoantigens / chemistry
  • Autoantigens / genetics
  • Autoantigens / metabolism*
  • Binding Sites
  • Carrier Proteins / metabolism*
  • Golgi Apparatus / metabolism*
  • Golgi Matrix Proteins
  • Green Fluorescent Proteins
  • HeLa Cells
  • Humans
  • Luminescent Proteins / genetics
  • Luminescent Proteins / metabolism
  • Membrane Proteins*
  • Mice
  • Molecular Sequence Data
  • Mutation
  • Protein Binding
  • Protein Structure, Tertiary
  • Recombinant Fusion Proteins / genetics
  • Recombinant Fusion Proteins / metabolism
  • Sequence Homology, Amino Acid
  • rab GTP-Binding Proteins*
  • ras Proteins / metabolism*

Substances

  • Autoantigens
  • Carrier Proteins
  • GOLGA4 protein, human
  • Golga4 protein, mouse
  • Golgi Matrix Proteins
  • Luminescent Proteins
  • Membrane Proteins
  • Rab6 protein
  • Recombinant Fusion Proteins
  • Green Fluorescent Proteins
  • rab GTP-Binding Proteins
  • ras Proteins