Mouse AMACO, a kidney and skin basement membrane associated molecule that mediates RGD-dependent cell attachment.
The VWA domain-containing extracellular matrix protein AMACO has not been extensively characterized and its function remains unknown. It has been proposed as a potential cancer marker and carries a rare O-glucosylation and O-fucosylation on its first EGF-like domain. AMACO is a basement membrane associated protein, however its exact localization has not been determined. Here we show by immunogold electron microscopy of mouse kidney and skin that AMACO does not occur within the basement membrane but rather subjacent to the basement membrane at its stromal surface. In skin, AMACO often colocalizes with triple-helical domains of collagen VII containing anchoring fibrils as they emerge from the basal lamina. However, the immunogold patterns for AMACO and the C-terminal end of collagen VII show discrete differences, indicating that AMACO and collagen VII do not colocalize at anchoring plaques. In contrast, the localization pattern of AMACO partially overlaps with that for collagen XVIII. In addition, mouse AMACO was shown to support beta1 integrin-mediated adhesion of a keratinocyte-like cell line, HaCaT, and a fibroblast cell line, Wi26, in an RGD-dependent manner, most likely using an RGD-motif near the C-terminus of AMACO. However, the loss of cell adhesion to the C-terminal part of the human AMACO, due to the unique absence of an RGD sequence in the human protein, suggests that cell adhesion is not AMACO's major function.
Gebauer
Jan M
JM
Center for Biochemistry, Medical Faculty, University of Cologne, D-50931 Cologne, Germany.
Keene
Douglas R
DR
Olsen
Bjorn R
BR
Sorokin
Lydia M
LM
Paulsson
Mats
M
Wagener
Raimund
R
D000818:Animals; D000831:Animals, Newborn; D000911:Antibodies, Monoclonal / Q000276:immunology / Q000494:pharmacology; D001485:Basement Membrane / Q000378:metabolism* / Q000648:ultrastructure; D014408:Biomarkers, Tumor; D002135:Calcium-Binding Proteins; D002413:Cations, Divalent / Q000494:pharmacology; D002448:Cell Adhesion / Q000187:drug effects / Q000502:physiology*; D002460:Cell Line; D024143:Collagen Type VII / Q000378:metabolism; D024102:Collagen Type VIII / Q000378:metabolism; D004622:Embryo, Mammalian / Q000378:metabolism; D016326:Extracellular Matrix Proteins / Q000235:genetics / Q000378:metabolism*; D005347:Fibroblasts / Q000166:cytology / Q000187:drug effects; D005353:Fibronectins / Q000378:metabolism; D006801:Humans; D019012:Integrin beta1 / Q000276:immunology / Q000378:metabolism; D015603:Keratinocytes / Q000166:cytology / Q000187:drug effects; D007668:Kidney / Q000254:growth & development / Q000378:metabolism* / Q000648:ultrastructure; D007672:Kidney Cortex / Q000378:metabolism; D007679:Kidney Medulla / Q000378:metabolism; D007684:Kidney Tubules / Q000378:metabolism / Q000648:ultrastructure; D051379:Mice; D008815:Mice, Inbred Strains; D009842:Oligopeptides / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism* / Q000494:pharmacology; D010446:Peptide Fragments / Q000235:genetics / Q000378:metabolism; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism; D012867:Skin / Q000196:embryology / Q000254:growth & development / Q000378:metabolism* / Q000648:ultrastructure
D000911:Antibodies, Monoclonal; D014408:Biomarkers, Tumor; D002135:Calcium-Binding Proteins; D002413:Cations, Divalent; D024143:Collagen Type VII; D024102:Collagen Type VIII; D016326:Extracellular Matrix Proteins; D005353:Fibronectins; D019012:Integrin beta1; D009842:Oligopeptides; D010446:Peptide Fragments; D011994:Recombinant Proteins; C480232:Vwa2 protein, mouse; C047981:arginyl-glycyl-aspartic acid; C049554:glycyl-arginyl-glycyl-aspartyl-serine