Filamin A Orchestrates Cytoskeletal Structure, Cell Migration and Stem Cell Characteristics in Human Seminoma TCam-2 Cells
Harald Welter,
Carola Herrmann,
Thomas Fröhlich,
Florian Flenkenthaler,
Katja Eubler,
Hubert Schorle,
Daniel Nettersheim,
Artur Mayerhofer,
Annette Müller-Taubenberger
Affiliations
Harald Welter
Anatomy III, Cell Biology, Biomedical Center, Ludwig Maximillian University of Munich, 82152 Planegg, Martinsried, Germany
Carola Herrmann
Anatomy III, Cell Biology, Biomedical Center, Ludwig Maximillian University of Munich, 82152 Planegg, Martinsried, Germany
Thomas Fröhlich
Laboratory for Functional Genome Analysis (LAFUGA), Gene Center, Ludwig Maximilian University of Munich, 81377 Munich, Germany
Florian Flenkenthaler
Laboratory for Functional Genome Analysis (LAFUGA), Gene Center, Ludwig Maximilian University of Munich, 81377 Munich, Germany
Katja Eubler
Anatomy III, Cell Biology, Biomedical Center, Ludwig Maximillian University of Munich, 82152 Planegg, Martinsried, Germany
Hubert Schorle
Department of Developmental Pathology, Institute of Pathology, University Hospital Bonn, 53127 Bonn, Germany
Daniel Nettersheim
Department of Urology, Urological Research Lab, Translational UroOncology, University Hospital Düsseldorf, Heinrich Heine University Düsseldorf, 40225 Düsseldorf, Germany
Artur Mayerhofer
Anatomy III, Cell Biology, Biomedical Center, Ludwig Maximillian University of Munich, 82152 Planegg, Martinsried, Germany
Annette Müller-Taubenberger
Anatomy III, Cell Biology, Biomedical Center, Ludwig Maximillian University of Munich, 82152 Planegg, Martinsried, Germany
Filamins are large dimeric F-actin cross-linking proteins, crucial for the mechanosensitive properties of a number of cell types. Due to their interaction with a variety of different proteins, they exert important regulatory functions. However, in the human testis the role of filamins has been insufficiently explored. Immunohistochemical staining of human testis samples identified filamin A (FLNA) in spermatogonia and peritubular myoid cells. Investigation of different testicular tumor samples indicated that seminoma also express FLNA. Moreover, mass spectrometric analyses identified FLNA as one of the most abundant proteins in human seminoma TCam-2 cells. We therefore focused on FLNA in TCam-2 cells, and identified by co-immunoprecipitation LAD1, RUVBL1 and DAZAP1, in addition to several cytoskeletal proteins, as interactors of FLNA. To study the role of FLNA in TCam-2 cells, we generated FLNA-deficient cells using the CRISPR/Cas9 system. Loss of FLNA causes an irregular arrangement of the actin cytoskeleton and mechanical instability, impaired adhesive properties and disturbed migratory behavior. Furthermore, transcriptional activity of typical stem cell factors is increased in the absence of FLNA. In summary, our data suggest that FLNA is crucially involved in balancing stem cell characteristics and invasive properties in human seminoma cells and possibly human testicular germ cells.
