The Journal of Cell Biology, Vol 73, 479-491, Copyright © 1977 by The Rockefeller University Press

ARTICLES

Dynamic aspects of filopodial formation by reorganization of microfilaments

KT Edds

The coelomocytes of the sea urchin, Strongylocentrotus droebachiensis, may be prevented from clotting with 50 mM ethylene glycol-bis(beta- aminoethyl)-N,N,N',N'-tetraacetate, 50 mM Tris-HCl, pH 7.8 and subsequently separated into various cell types on sucrose gradients. One cell type, the petaloid coelomocyte, spontaneously undergoes a striking morphological transformation to a form exhibiting numerous, t- in cytoplasmic projections (filopodia). Moreover, the transformation is reversible. Ultrastructurally, the formation of the filopodia results from a progressive reorganization of actin-containing filaments into bundles that are radially oriented. The formation of the filament bundles is initiated at the cell's periphery and proceeds inward. Simultaneously, the cytoplasm in between the bundles is withdrawn, exposing finger-like filopodia. Ultimately, the filopodia can be extended by up to four times their original length. Biochemically, actin is the most abundant protein in while cell homogenates and is extractable in milligram quantities via acetone powders. An actomyosin complex may also be isolated from these cells and is presumed to be active in producing the various forms of motility observed.
CiteULike    Complore    Connotea    Del.icio.us    Digg    Facebook    Reddit    Technorati    Twitter    What's this?

This article has been cited by other articles:

• Brockton, V., Henson, J. H., Raftos, D. A., Majeske, A. J., Kim, Y.-O., Smith, L. C. (2008). Localization and diversity of 185/333 proteins from the purple sea urchin - unexpected protein-size range and protein expression in a new coelomocyte type. J. Cell Sci. 121: 339-348 [Abstract] [Full Text]  
• Browne, C. L., Swan, J. B., Rankin, E. E., Calvert, H., Griffiths, S., Tytell, M. (2007). Extracellular heat shock protein 70 has novel functional effects on sea urchin eggs and coelomocytes. J. Exp. Biol. 210: 1275-1287 [Abstract] [Full Text]  
• Hillier, B. J., Vacquier, V. D. (2003). Amassin, an olfactomedin protein, mediates the massive intercellular adhesion of sea urchin coelomocytes. JCB 160: 597-604 [Abstract] [Full Text]  
• Steketee, M., Balazovich, K., Tosney, K. W. (2001). Filopodial Initiation and a Novel Filament-organizing Center, the Focal Ring. Mol. Biol. Cell 12: 2378-2395 [Abstract] [Full Text]  
• Smith, L. C., Shih, C.-S., Dachenhausen, S. G. (1998). Coelomocytes Express SpBf, a Homologue of Factor B, the Second Component in the Sea Urchin Complement System. J. Immunol. 161: 6784-6793 [Abstract] [Full Text]  
• Seastone, D. J., Lee, E., Bush, J., Knecht, D., Cardelli, J. (1998). Overexpression of a Novel Rho Family GTPase, RacC, Induces Unusual Actin-based Structures and Positively Affects Phagocytosis in Dictyostelium discoideum. Mol. Biol. Cell 9: 2891-2904 [Abstract] [Full Text]  
• D'Andrea, L, Danon, M., Sgourdas, G., Bonder, E. (1994). Identification of coelomocyte unconventional myosin and its association with in vivo particle/vesicle motility. J. Cell Sci. 107: 2081-2094 [Abstract]  
• Henson, J. H., Nesbitt, D., Wright, B. D., Scholey, J. M. (1992). Immunolocalization of kinesin in sea urchin coelomocytes. Association of kinesin with intracellular organelles. J. Cell Sci. 103: 309-320 [Abstract]  
• DeRosier, D. J., Tilney, L. G. (1982). How Actin Filaments Pack into Bundles. Cold Spring Harb Symp Quant Biol 46: 525-540 [Abstract]  
• Small, J. V., Rinnerthaler, G., Hinssen, H. (1982). Organization of Actin Meshworks in Cultured Cells: The Leading Edge. Cold Spring Harb Symp Quant Biol 46: 599-611 [Abstract]  

Home | Help | Feedback | Subscriptions | Archive | Search | Table of Contents