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Fimbrin
Fimbrin also known as is plastin 1 is a protein that in humans is encoded by the PLS1 gene. Fimbrin is an actin cross-linking protein important in the formation of filopodia. Structure Fimbrin belongs to the calponin homology (CH) domain superfamily of actin cross-linking proteins. Like other members of this superfamily, which include α-actinin, β-spectrin, dystrophin, ABP-120 and filamin, it has a conserved 27 kDa actin-binding domain that contains a tandem duplication of a sequence that is homologous to calponin. In addition to cross-linking actin filaments into bundles and networks, CH domains also bind intermediate filaments and some signal transduction proteins to the actin cytoskeleton. Structural comparison of actin filaments and fimbrin CH domain-decorated actin filaments has revealed changes in the actin structure due to fimbrin-mediated cross-linking that may affect the actin filaments' affinity for other actin-binding proteins and may be part of the regulation of th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Filopodia
Filopodia (singular filopodium) are slender cytoplasmic projections that extend beyond the leading edge of lamellipodia in migrating cells. Within the lamellipodium, actin ribs are known as ''microspikes'', and when they extend beyond the lamellipodia, they're known as filopodia. They contain microfilaments (also called actin filaments) cross-linked into bundles by actin-bundling proteins, such as fascin and fimbrin. Filopodia form focal adhesions with the substratum, linking them to the cell surface. Many types of migrating cells display filopodia, which are thought to be involved in both sensation of chemotropic cues, and resulting changes in directed locomotion. Activation of the Rho family of GTPases, particularly cdc42 and their downstream intermediates, results in the polymerization of actin fibers by Ena/Vasp homology proteins. Growth factors bind to receptor tyrosine kinases resulting in the polymerization of actin filaments, which, when cross-linked, make up the sup ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |