It is worthy of note that the expression of fascin is highly specific to tissue and cell types. These observations suggest the involvement of fascin in the formation of actin bundles present in filopodia, microspikes, membrane ruffles, and stress fibers. Fascin is also found in microspikes during spreading of a variety of cells including glioma cells ( Lin et al., 1996) and myoblasts ( Adams, 1995, 1997). We have purified fascin (55-kDa actin-bundling protein) from HeLa cells ( Yamashiro-Matsumura and Matsumura, 1985), and found that this human protein is localized mainly at filopodia and membrane ruffles, as well as in stress fibers ( Yamashiro-Matsumura and Matsumura, 1986). Sea urchin fascin is involved in the formation of filopodia by coelomocytes, the phagocytotic defense cells of echinoderms ( Otto et al., 1979) and may act in the formation of microvillar cores at fertilization ( Otto et al., 1980). Subsequent cloning of human, mouse, and Xenopus fascins ( Duh et al., 1994 Holthuis et al., 1994 Mosialos et al., 1994 Edward et al., 1995) has revealed that the amino acid sequences of these fascin proteins are very similar to each other but share no apparent homology with nonfascin actin-bundling proteins (including villin and fimbrin), indicating that the fascins represent a distinct family of actin-binding proteins.Īll of the fascin proteins cause aggregation of F-actin into bundles in vitro, the property of which is reflected to the localization of fascin in a variety of cells. Bryan and co-workers has shown that fascin has 35% identity at the amino acid level to the product of the Drosophila singed gene ( Bryan et al., 1993). Molecular cloning of sea urchin fascin by J. Fascin is evolutionarily conserved, although yeast does not seem to have a fascin homolog. These results together suggest that fascin is directly responsible for membrane protrusions through reorganization of the microfilament cytoskeleton at the cell periphery.įascins represent a family of actin-bundling proteins including sea urchin fascin, HeLa 55-kDa actin-bundling protein, and the Drosophila singed protein ( Matsudaira, 1994 Otto, 1994 Edwards and Bryan, 1995). Furthermore, microinjection of fascin into REF-52 cells, normal fibroblasts, induces the formation of many lamellipodia at all regions of cell periphery. Microinjection of a fascin protein into LLC-PK1 cells causes similar morphological alterations including the induction of lamellipodia at basolateral surfaces and formation of an increased number of microvilli on apical surfaces. Cell migration activity is increased by 8–17 times when assayed by modified Boyden chamber. Expression of fascin results in large changes in morphology, the actin cytoskeleton, and cell motility: fascin-transfected cells form an increased number of longer and thicker microvilli on apical surfaces, extend lamellipodia-like structures at basolateral surfaces, and show disorganization of cell–cell contacts. To examine whether fascin contributes to the alterations in microfilament organization at the cell periphery, we have expressed fascin in LLC-PK1 epithelial cells to levels as high as those found in transformed cells and in specialized normal cells.
A morphological characteristic common to these cells expressing high levels of fascin is the development of many membrane protrusions in which fascin is predominantly present.
The expression of fascin is greatly increased in many transformed cells, as well as in specialized normal cells including neuronal cells and antigen-presenting dendritic cells. It does not store any personal data.Fascin is an actin-bundling protein that is found in membrane ruffles, microspikes, and stress fibers. The cookie is set by the GDPR Cookie Consent plugin and is used to store whether or not user has consented to the use of cookies. The cookie is used to store the user consent for the cookies in the category "Performance". This cookie is set by GDPR Cookie Consent plugin. The cookie is used to store the user consent for the cookies in the category "Other. The cookies is used to store the user consent for the cookies in the category "Necessary". The cookie is set by GDPR cookie consent to record the user consent for the cookies in the category "Functional". The cookie is used to store the user consent for the cookies in the category "Analytics".
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