title: Occurrence of fibers and their association with talin in the cleavage furrows of PtK2 cells.
abstract: PtK2 cells of exceptionally large size were microinjected with fluorescently labeled probes for actin, myosin, filamin, and talin in order to follow the assembly of the contractile proteins into the cleavage furrows. Whereas in cells of normal size, there is usually a diffuse pattern of localization of proteins in the cleavage furrow, in these large, flat cells the labeled proteins localized in fibers in the cleavage furrow. Often, the fibers were striated in a pattern comparable to that measured in the stress fibers of the same cell type. The presence of talin in discrete plaques along fibers in the cleavage furrows of the large cells suggests a further similarity between cleavage furrow and stress fiber structure. The presence of filamin in the cleavage furrows also suggests the possibility of an overlapping mechanism in addition to that of a talin mediated mechanism for the attachment of actin filaments to the cell surfaces in the cleavage furrow. A model is presented that emphasizes the interrelationships between stress fibers, myofibrils, and cleavage furrows.
authors.affiliation: Department of Cell and Developmental Biology, University of Pennsylvania School of Medicine, Philadelphia.
authors.forename: J M
authors.initials: JM
authors.lastname: Sanger
authors.forename: J S
authors.initials: JS
authors.lastname: Dome
authors.forename: R S
authors.initials: RS
authors.lastname: Hock
authors.forename: B
authors.initials: B
authors.lastname: Mittal
authors.forename: J W
authors.initials: JW
authors.lastname: Sanger
mesh_terms: D008841:Actin Cytoskeleton / Q000737:chemistry / Q000648:ultrastructure*; D000199:Actins / Q000032:analysis; D000818:Animals; D002460:Cell Line; D003285:Contractile Proteins / Q000032:analysis; D004848:Epithelium / Q000648:ultrastructure; D064448:Filamins; D005456:Fluorescent Dyes; D007091:Image Processing, Computer-Assisted; D007668:Kidney / Q000166:cytology*; D007614:Macropodidae; D008840:Microfilament Proteins / Q000032:analysis; D008845:Microinjections; D009218:Myosins / Q000032:analysis; D016608:Talin / Q000032:analysis*; D013692:Telophase
chemical_list: D000199:Actins; D003285:Contractile Proteins; D064448:Filamins; D005456:Fluorescent Dyes; D008840:Microfilament Proteins; D016608:Talin; D009218:Myosins