High impact information on LOC395261

• TW 260/240 is quite distinct from smooth muscle filamin and macrophage actin-binding protein (APB), but, in spite of its higher contour length (265 nm), seems to be related to erythrocyte spectrin (194 nm for the tetramer) [1].
• The synthesis and deployment of filamin in chicken skeletal muscle [2].
• By use of light microscopy and fluorescence photobleaching recovery, we have studied (a) structures that form in a system composed of copolymerized rabbit muscle actin and chicken gizzard filamin and (b) the Brownian motion of inert tracer macromolecules in this matrix [3].
• The cytoskeleton, marked by antibodies to desmin and filamin is composed of a mainly longitudinal, meandering and branched system of fibrils that contrasts with the plait-like, interdigitating arrangement of linear fibrils of the contractile apparatus, labeled with antibodies to myosin and tropomyosin [4].
• Membrane extracts from chicken smooth muscle contain, along with filamin, vinculin and alpha actinin, a group of polypeptides that have the ability to interact with the "barbed end" of actin filaments [5].

Biological context of LOC395261

• The analysis showed that the protein revealed significant homology with the rod region of chicken filamin (57% homology in amino acid sequence) [6].
• Purification and properties of filamin, and actin binding protein from chicken gizzard [7].
• Characterization of the actin binding site on smooth muscle filamin [8].
• Gel-sol transformation of actin filaments, a process essential for cell motility, can be reconstituted in vitro and regulated in a predictable fashion by the combined action of villin and filamin [9].
• In cosedimentation experiments, phosphorylation reduces the binding of filamin to actin filaments [10].

Anatomical context of LOC395261

• Filamin was found to be localized specifically in the latter intermediate filament-actin domains, but was excluded from the core of the dense bodies [11].
• Cytoskeletal components of the vertebrate neuromuscular junction: vinculin, alpha-actinin, and filamin [12].
• The antibody was shown to bind only chick embryo cell filamin when whole cell extracts were analyzed by the sensitive sodium dodecyl sulfate-polyacrylamide gel electrophoresis overlay technique described by Adair et al [13].
• In cultured cells, filamin was found largely to be arranged as a filamentous array very similar to that found for myosin [14].
• Localization of a filamin-like protein in glia of the chick central nervous system [15].

Associations of LOC395261 with chemical compounds

• The major proteins remaining in the ghosts comigrate, on polyacrylamide gels in the presence of SDS, with chicken gizzard actin, myosin, filamin, and a 110-kdalton protein [16].
• We have isolated an NH2-terminal fragment of filamin (M(r) = 70,000) after digestion with Staphylococus aureus V8 protease [8].
• On sodium dodecyl sulfate gel electrophoresis, filamin migrates as a single protein band with an estimated molecular weight of 240,000 [7].
• We have found that purified chicken gizzard filamin is phosphorylated in vitro at serine residues by the Ca2+/calmodulin-dependent protein kinase II (CaM kinase II) [10].
• On the other hand, leupeptin, which can also inhibit calpain in vitro but can not penetrate into cells, showed little or no effect on both myoblast fusion and filamin clevage [17].

Physical interactions of LOC395261

• Caldesmon decreased the binding constant of filamin with F-actin [18].
• FAP52 binds to filamin via its N-terminal alpha-helical domain, suggesting a role in linking focal adhesions to the actin-based cytoskeleton [19].

Regulatory relationships of LOC395261

• Villin inhibits filamin-induced F-actin gelation, but the effect can be overcome by increasing the amount of filamin [9].
• However, a time course of agrin-induced clustering that focused on filamin revealed that most of the early AChR clusters (3-6 h) were not associated with detectable amounts of cytoskeletal material [20].
• From these results, caldesmon and tropomyosin appeared to influence filamin binding to F-actin with different modes of actin [18].

Other interactions of LOC395261

• Unlike other focal adhesion proteins, such as vinculin and talin, this filamin isoform is apparently not localized evenly throughout the entire area of adhesion, being absent from or greatly reduced in the distal portion of the area [21].
• Filamin cross-links F-actin into networks that are more resilient, stiffer, more solid-like, and less dynamic than alpha-actinin and fascin [22].
• Sedimentation assays show that villin does not inhibit gelation of actin by preventing filamin from binding to F-actin [9].
• Reconstitution of Ca2+-sensitive gelation of actin filaments with filamin, caldesmon and calmodulin [23].
• We determined the full cDNA sequences of chicken gizzard filamin and cgABP260 (chicken gizzard actin-binding protein 260) [24].

Analytical, diagnostic and therapeutic context of LOC395261

• Immunofluorescence and electron microscopic studies suggest that the F-actin filaments are collected into fiber bundles and a crosslinked fiber meshwork by the binding of filamin molecules [25].
• However, filamin binds to rabbit skeletal muscle F-actin, and the complex is readily sedimented by centrifugation to yield a gelatinous pellet containing actin and filamin [7].
• The proteins are then fractionated by Mg2+- and (NH4)2SO4-induced precipitations and by ion exchange and gel filtration column chromatography to give rise to highly purified preparations of alpha-actinin, filamin, and a 130,000-dalton protein [26].
• With use of the indirect immunofluorescence technique, the filamin antibody localized in the Z-line region of chicken skeletal muscle myofibrils [27].
• The interactions of actin filaments with actin-binding protein (filamin) and caldesmon under the influence of tropomyosin were studied in detail using falling-ball viscometry, binding assay and electron microscopy [18].

References