Interactions of phocein with nucleoside-diphosphate kinase, Eps15, and Dynamin I.
Phocein, an intracellular protein interacting with striatin, bears a few homologies with the sigma-subunits of clathrin adaptor proteins (Baillat, G., Moqrich, A., Castets, F., Baude, A., Bailly, Y., Benmerah, A., and Monneron, A. (2001) Mol. Biol. Cell 12, 663-673). Using phocein as a bait in a yeast two-hybrid screen, we identified two novel interacting proteins, nucleoside-diphosphate kinase (NDPK) and Eps15. Immunoprecipitation and pull-down experiments involving native and/or recombinant phocein and, respectively, NDPK and Eps15, biochemically validated their interactions. NDPK and Eps15 were recently shown to be functional neighbors of dynamin. Dynamin I is shown here to directly interact with NDPK through its C-terminal proline-rich domain, whereas recombinant phocein associates with native dynamin I. Immunocytochemical studies of rat embryonic hippocampal neurons demonstrated partial co-localization of phocein and dynamin I. Phocein thus appears to be a component of the complexes involved in some steps of the vesicular traffic machinery.
Baillat
Gilbert
G
INSERM U464, Faculté de Médecine Nord, Bd. Pierre Dramard, 13916 Marseille Cedex 20, France.
Gaillard
Stephane
S
Castets
Francis
F
Monneron
Ariane
A
D000818:Animals; D001921:Brain / Q000201:enzymology / Q000378:metabolism; D002135:Calcium-Binding Proteins / Q000378:metabolism*; D034284:Dynamin I; D034281:Dynamins; D020558:GTP Phosphohydrolases / Q000378:metabolism*; D008565:Membrane Proteins / Q000378:metabolism*; D009701:Nucleoside-Diphosphate Kinase / Q000378:metabolism*; D010750:Phosphoproteins / Q000378:metabolism*; D011485:Protein Binding; D051381:Rats; D017208:Rats, Wistar; D020798:Two-Hybrid System Techniques
D002135:Calcium-Binding Proteins; D008565:Membrane Proteins; D010750:Phosphoproteins; C430214:phocein; D009701:Nucleoside-Diphosphate Kinase; D034284:Dynamin I; D020558:GTP Phosphohydrolases; D034281:Dynamins