title: The SCAR/WAVE complex is necessary for proper regulation of traction stresses during amoeboid motility.
abstract: Cell migration requires a tightly regulated, spatiotemporal coordination of underlying biochemical pathways. Crucial to cell migration is SCAR/WAVE-mediated dendritic F-actin polymerization at the cell's leading edge. Our goal is to understand the role the SCAR/WAVE complex plays in the mechanics of amoeboid migration. To this aim, we measured and compared the traction stresses exerted by Dictyostelium cells lacking the SCAR/WAVE complex proteins PIR121 (pirA(-)) and SCAR (scrA(-)) with those of wild-type cells while they were migrating on flat, elastic substrates. We found that, compared to wild type, both mutant strains exert traction stresses of different strengths that correlate with their F-actin levels. In agreement with previous studies, we found that wild-type cells migrate by repeating a motility cycle in which the cell length and strain energy exerted by the cells on their substrate vary periodically. Our analysis also revealed that scrA(-) cells display an altered motility cycle with a longer period and a lower migration velocity, whereas pirA(-) cells migrate in a random manner without implementing a periodic cycle. We present detailed characterization of the traction-stress phenotypes of the various cell lines, providing new insights into the role of F-actin polymerization in regulating cell-substratum interactions and stresses required for motility.
authors: Department of Bioengineering, Jacobs School of Engineering, University of California, San Diego, La Jolla, CA 92093, USA.
authors: Effie
authors: E
authors: Bastounis
authors: Ruedi
authors: R
authors: Meili
authors: Baldomero
authors: B
authors: Alonso-Latorre
authors: Juan C
authors: JC
authors: del Álamo
authors: Juan C
authors: JC
authors: Lasheras
authors: Richard A
authors: RA
authors: Firtel
mesh_terms: D000199:Actins / Q000378:metabolism; D001696:Biomechanical Phenomena; D016764:Cell Polarity; D002633:Chemotaxis; D003712:Dendrites / Q000378:metabolism; D004023:Dictyostelium / Q000166:cytology / Q000235:genetics / Q000502:physiology*; D055786:Gene Knockout Techniques; D007700:Kinetics; D015800:Protozoan Proteins / Q000235:genetics / Q000378:metabolism*; D013314:Stress, Mechanical; D059008:Time-Lapse Imaging; D051300:Wiskott-Aldrich Syndrome Protein Family / Q000235:genetics / Q000378:metabolism*
chemical_list: D000199:Actins; D015800:Protozoan Proteins; C491975:SCAR protein, Dictyostelium; D051300:Wiskott-Aldrich Syndrome Protein Family