Re-arrangements of podosome structures are observed when Hck is activated in myeloid cells.
Podosomes are adhesion structures with an extracellular matrix-degrading capacity mostly found in monocyte-derived cells. We have previously shown that the protein tyrosine kinase Hck, a member of the Src family, triggers the de novo formation of podosome rosettes in a lysosome-dependent manner when expressed in its constitutively active form. Hck is specifically expressed in myeloid cells. In human monocyte-derived macrophages (MDMs) it is present at podosomes. Here we addressed whether its activation by lipopolysaccharide and interferon-gamma has an effect on podosome organization in MDMs. Several structures were observed evolving from individual podosomes to clusters, aggregates and rosettes. In chronic myeloid leukemia cells, Hck is constitutively activated by the fusion protein Bcr-Abl and podosome-like structures were present. Finally, in monocyte-derived osteoclasts, Hck was found to accumulate at podosome belts. In conclusion, in monocyte-derived cells, it is likely that Hck could play a role in podosome re-arrangements.
CNRS UMR5089, Institut de Pharmacologie et de Biologie Structurale, 205 route de Narbonne, F-31077 Toulouse Cedex, France.
Renaud
R
Poincloux
Claire
C
Vincent
Arnaud
A
Labrousse
Jerôme
J
Castandet
Maxime
M
Rigo
Céline
C
Cougoule
Christine
C
Bordier
Véronique
V
Le Cabec
Isabelle
I
Maridonneau-Parini
D008841:Actin Cytoskeleton / Q000648:ultrastructure*; D000818:Animals; D015815:Cell Adhesion Molecules / Q000378:metabolism; D002462:Cell Membrane / Q000378:metabolism; D002478:Cells, Cultured; D005455:Fluorescent Antibody Technique; D016313:Genes, abl; D006801:Humans; D007371:Interferon-gamma / Q000378:metabolism / Q000494:pharmacology; D020014:K562 Cells; D008070:Lipopolysaccharides / Q000378:metabolism / Q000494:pharmacology; D022423:Myeloid Cells / Q000201:enzymology* / Q000648:ultrastructure*; D010010:Osteoclasts / Q000166:cytology / Q000378:metabolism; D051572:Proto-Oncogene Proteins c-hck / Q000378:metabolism*; D014407:Tumor Cells, Cultured
D015815:Cell Adhesion Molecules; D008070:Lipopolysaccharides; D007371:Interferon-gamma; C496631:HCK protein, human; D051572:Proto-Oncogene Proteins c-hck