The armadillo repeat region targets ARVCF to cadherin-based cellular junctions.
The cytoplasmic domain of the transmembrane protein M-cadherin is involved in anchoring cytoskeletal elements to the plasma membrane at cell-cell contact sites. Several members of the armadillo repeat protein family mediate this linkage. We show here that ARVCF, a member of the p120 (ctn) subfamily, is a ligand for the cytoplasmic domain of M-cadherin, and characterize the regions involved in this interaction in detail. Complex formation in an in vivo environment was demonstrated in (1) yeast two-hybrid screens, using a cDNA library from differentiating skeletal muscle and part of the cytoplasmic M-cadherin tail as a bait, and (2) mammalian cells, using a novel experimental system, the MOM recruitment assay. Immunoprecipitation and in vitro binding assays confirmed this interaction. Ectopically expressed EGFP-ARVCF-C11, an N-terminal truncated fragment, targets to junctional structures in epithelial MCF7 cells and cardiomyocytes, where it colocalizes with the respective cadherins, beta-catenin and p120 (ctn). Hence, the N terminus of ARVCF is not required for junctional localization. In contrast, deletion of the four N-terminal armadillo repeats abolishes this ability in cardiomyocytes. Detailed mutational analysis revealed the armadillo repeat region of ARVCF as sufficient and necessary for interaction with the 55 membrane-proximal amino acids of the M-cadherin tail.
Kaufmann
U
U
Institut der Anthropologie und Humangenetik fuer Biologen, Johann-Wolfgang-Goethe-Universitaet Frankfurt, Siesmayerstrasse 70, D-60054 Frankfurt/Main, Germany.
Zuppinger
C
C
Waibler
Z
Z
Rudiger
M
M
Urbich
C
C
Martin
B
B
Jockusch
B M
BM
Eppenberger
H
H
Starzinski-Powitz
A
A
D000595:Amino Acid Sequence; D000818:Animals; D051186:Armadillo Domain Proteins; D001665:Binding Sites; D015820:Cadherins / Q000737:chemistry / Q000378:metabolism*; D015815:Cell Adhesion Molecules / Q000737:chemistry* / Q000378:metabolism*; D002462:Cell Membrane / Q000502:physiology / Q000648:ultrastructure; D002478:Cells, Cultured; D006352:Heart Ventricles; D006801:Humans; D007365:Intercellular Junctions / Q000502:physiology* / Q000648:ultrastructure; D008024:Ligands; D051379:Mice; D008969:Molecular Sequence Data; D009132:Muscles / Q000166:cytology / Q000502:physiology* / Q000648:ultrastructure*; D009206:Myocardium / Q000648:ultrastructure; D010750:Phosphoproteins / Q000737:chemistry* / Q000378:metabolism*; D011994:Recombinant Proteins / Q000378:metabolism; D020449:Repetitive Sequences, Amino Acid; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid; D014162:Transfection
C411307:ARVCF protein, human; D051186:Armadillo Domain Proteins; C485846:Arvcf protein, mouse; D015820:Cadherins; D015815:Cell Adhesion Molecules; D008024:Ligands; D010750:Phosphoproteins; D011994:Recombinant Proteins; C070896:M-cadherin