The multifunctional protein GC1q-R interacts specifically with the i3 loop arginine cluster of the vasopressin V2 receptor.
In this study, we identified the multifunctional protein GC1q-R as a novel vasopressin V(2) receptor (V(2)R) interacting protein. For this purpose, we have developed a proteomic approach combining pull-down assays using a cyclic peptide mimicking the third intracellular loop of V(2)R as a bait and mass spectrometry analyses of proteins isolated from either rat or human kidney tissues or the HEK 293 cell line. Co-immunoprecipitation of GC1q-R with the c-Myc-tagged h-V(2)R expressed in a HEK cell line confirmed the existence of a specific interaction between GC1q-R and the V(2) receptor. Then, construction of a mutant receptor in i3 loop allowed us to identify the i3 loop arginine cluster of the vasopressin V(2) receptor as the interacting determinant for GC1q-R interaction. Using purified receptor as a bait and recombinant (74-282) GC1q-R, we demonstrated a direct and specific interaction between these two proteins via the arginine cluster.
Granier
Sébastien
S
CNRS, UMR 5203, Institut de Génomique fonctionnelle, Montpellier, France.
Jean-Alphonse
Frédéric
F
Bacqueville
Daniel
D
Monteil
Arnaud
A
Pascal
Robert
R
Poncet
Joël
J
Guillon
Gilles
G
Boudier
Laure
L
Arcemisbéhère
Laure
L
Mouillac
Bernard
B
Bellot
Gaétan
G
Déméné
Hélène
H
Mendre
Christiane
C
D000328:Adult; D000595:Amino Acid Sequence; D000818:Animals; D001120:Arginine / Q000737:chemistry / Q000378:metabolism*; D002352:Carrier Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D002460:Cell Line; D006801:Humans; D007668:Kidney / Q000378:metabolism; D008875:Middle Aged; D024101:Mitochondrial Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D008954:Models, Biological; D008969:Molecular Sequence Data; D011485:Protein Binding; D051381:Rats; D017483:Receptors, Vasopressin / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D011994:Recombinant Proteins / Q000737:chemistry / Q000378:metabolism; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
C087299:C1QBP protein, human; D002352:Carrier Proteins; D024101:Mitochondrial Proteins; D017483:Receptors, Vasopressin; D011994:Recombinant Proteins; D001120:Arginine