Interaction between p230 and MACF1 is associated with transport of a glycosyl phosphatidyl inositol-anchored protein from the Golgi to the cell periphery

Exp Cell Res. 2004 Aug 15;298(2):388-98. doi: 10.1016/j.yexcr.2004.04.047.

Abstract

The molecular basis by which proteins are transported along cytoskeletal tracts from the trans-Golgi network (TGN) to the cell periphery remains poorly understood. Previously, using human autoimmune sera, we identified and characterized a TGN protein, p230/Golgin-245, an extensively coiled-coil protein with flexible amino- and carboxyl-terminal ends, that is anchored to TGN membranes and TGN-derived vesicles by its carboxyl-terminal GRIP domain. To identify molecules that interact with the flexible amino-terminal end of p230, we used this domain as bait to screen a human brain cDNA library in a yeast two-hybrid assay. We found that this domain interacts with the carboxyl-terminal domain of MACF1, a protein that cross-links microtubules to the actin cytoskeleton. The interaction was confirmed by co-immunoprecipitation, an in vitro binding assay, double immunofluorescence images demonstrating overlapped localization in HeLa cells, and co-localization of FLAG-tagged constructs containing the interacting domains of these two proteins with their endogenous partners. Expression in HeLa cells of FLAG-tagged constructs containing the interacting domains of p230 and MACF1 disrupted transport of the glycosyl phosphatidyl inositol-anchored marker protein conjugated with yellow fluorescent protein (YFP-SP-GPI), while trafficking of the transmembrane marker protein, vesicular stomatitis virus glycoprotein conjugated with YFP (VSVG3-GL-YFP), was unaffected. Our results suggest that p230, through its interaction with MACF1, provides the molecular link for transport of GPI-anchored proteins along the microtubule and actin cytoskeleton from the TGN to the cell periphery.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence / physiology
  • Autoantigens / metabolism*
  • Bacterial Proteins
  • Cell Membrane / metabolism*
  • Cell Membrane / ultrastructure
  • Cytoskeleton / metabolism
  • Cytoskeleton / ultrastructure
  • Glycosylphosphatidylinositols / metabolism*
  • Golgi Apparatus / metabolism*
  • Golgi Apparatus / ultrastructure
  • HeLa Cells
  • Humans
  • Luminescent Proteins
  • Membrane Proteins / metabolism*
  • Microfilament Proteins / metabolism*
  • Microtubules / genetics
  • Molecular Sequence Data
  • Protein Binding / genetics
  • Protein Structure, Tertiary / genetics
  • Protein Transport / physiology
  • Recombinant Fusion Proteins / genetics
  • Recombinant Fusion Proteins / metabolism

Substances

  • Autoantigens
  • Bacterial Proteins
  • GOLGA4 protein, human
  • Glycosylphosphatidylinositols
  • Luminescent Proteins
  • MACF1 protein, human
  • Membrane Proteins
  • Microfilament Proteins
  • Recombinant Fusion Proteins
  • yellow fluorescent protein, Bacteria