Disruption of microfilament organization in living nonmuscle cells by microinjection of plasma vitamin D-binding protein or DNase I. 1990

J M Sanger, and G Dabiri, and B Mittal, and M A Kowalski, and J G Haddad, and J W Sanger
Department of Anatomy, University of Pennsylvania, School of Medicine, Philadelphia 19104-6058.

Plasma vitamin D-binding protein (DBP), which binds to monomeric actin, causes the breakdown of stress fibers when it is microinjected into nonmuscle cells. Disruption of the stress fiber network is also accompanied by shape changes in the cell that resemble those seen after cytochalasin treatment. When DBP was coinjected with fluorescently labeled alpha-actinin, no fluorescent stress fibers or attachment plaques were visible 30 min after injection. Twelve hours later the cells regained their flattened shape and their stress fibers. Fluorescently labeled DBP causes the same reversible changes in cell shape as the unlabeled protein. Upon injection, the labeled DBP diffuses throughout the cytoplasm, becoming localized by 12 hr in a punctate pattern, presumably due to lysozomal sequestration. Similar injections of DBP into skeletal myotubes and cardiac myocytes did not lead to shape changes or breakdown of nascent and/or fully formed myofibrils, even though DBP has a 2-fold higher binding affinity for muscle actin over that of the nonmuscle isoactins. Similar differential effects in nonmuscle cells were also observed after the microinjection of DNase I, another protein capable of binding monomer actin. The effects of these microinjected monomer actin-binding proteins imply that an accessible pool of monomer actin is needed to maintain stress fiber integrity in nonmuscle cells but not the integrity of the nascent or fully formed myofibrils in muscle cells.

UI MeSH Term Description Entries
D007700 Kinetics The rate dynamics in chemical or physical systems.
D008841 Actin Cytoskeleton Fibers composed of MICROFILAMENT PROTEINS, which are predominately ACTIN. They are the smallest of the cytoskeletal filaments. Actin Filaments,Microfilaments,Actin Microfilaments,Actin Cytoskeletons,Actin Filament,Actin Microfilament,Cytoskeleton, Actin,Cytoskeletons, Actin,Filament, Actin,Filaments, Actin,Microfilament,Microfilament, Actin,Microfilaments, Actin
D008845 Microinjections The injection of very small amounts of fluid, often with the aid of a microscope and microsyringes. Microinjection
D002460 Cell Line Established cell cultures that have the potential to propagate indefinitely. Cell Lines,Line, Cell,Lines, Cell
D003599 Cytoskeleton The network of filaments, tubules, and interconnecting filamentous bridges which give shape, structure, and organization to the cytoplasm. Cytoplasmic Filaments,Cytoskeletal Filaments,Microtrabecular Lattice,Cytoplasmic Filament,Cytoskeletal Filament,Cytoskeletons,Filament, Cytoplasmic,Filament, Cytoskeletal,Filaments, Cytoplasmic,Filaments, Cytoskeletal,Lattice, Microtrabecular,Lattices, Microtrabecular,Microtrabecular Lattices
D003850 Deoxyribonuclease I An enzyme capable of hydrolyzing highly polymerized DNA by splitting phosphodiester linkages, preferentially adjacent to a pyrimidine nucleotide. This catalyzes endonucleolytic cleavage of DNA yielding 5'-phosphodi- and oligonucleotide end-products. The enzyme has a preference for double-stranded DNA. DNase I,Streptodornase,DNA Endonuclease,DNA Nicking Enzyme,DNAase I,Dornavac,Endonuclease I,Nickase,Pancreatic DNase,T4-Endonuclease II,T7-Endonuclease I,Thymonuclease,DNase, Pancreatic,Endonuclease, DNA,T4 Endonuclease II,T7 Endonuclease I
D000185 Actinin A protein factor that regulates the length of R-actin. It is chemically similar, but immunochemically distinguishable from actin. alpha-Actinin,Eu-Actinin,beta-Actinin,Eu Actinin,alpha Actinin,beta Actinin
D000818 Animals Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA. Animal,Metazoa,Animalia
D014617 Vacuoles Any spaces or cavities within a cell. They may function in digestion, storage, secretion, or excretion. Vacuole
D014809 Vitamin D-Binding Protein An alpha-globulin found in the plasma of man and other vertebrates. It is apparently synthesized in the liver and carries vitamin D and its metabolites through the circulation and mediates the response of tissue. It is also known as group-specific component (Gc). Gc subtypes are used to determine specific phenotypes and gene frequencies. These data are employed in the classification of population groups, paternity investigations, and in forensic medicine. Group-Specific Component Globulin,Vitamin D-Binding Globulin,25-HCC-Binding Protein,25-Hydroxycholecalciferol-Binding Protein,25-Hydroxyvitamin D-Binding Protein,Calciferol-Binding Protein,Gc Globulin,Transcalciferin,25 HCC Binding Protein,25 Hydroxycholecalciferol Binding Protein,25 Hydroxyvitamin D Binding Protein,Calciferol Binding Protein,Component Globulin, Group-Specific,Globulin, Gc,Globulin, Group-Specific Component,Globulin, Vitamin D-Binding,Group Specific Component Globulin,Vitamin D Binding Globulin,Vitamin D Binding Protein

Related Publications

J M Sanger, and G Dabiri, and B Mittal, and M A Kowalski, and J G Haddad, and J W Sanger
January 1995, Cell motility and the cytoskeleton,
J M Sanger, and G Dabiri, and B Mittal, and M A Kowalski, and J G Haddad, and J W Sanger
January 1996, European journal of cell biology,
J M Sanger, and G Dabiri, and B Mittal, and M A Kowalski, and J G Haddad, and J W Sanger
November 1991, Biochemical Society transactions,
J M Sanger, and G Dabiri, and B Mittal, and M A Kowalski, and J G Haddad, and J W Sanger
September 1978, The journal of histochemistry and cytochemistry : official journal of the Histochemistry Society,
J M Sanger, and G Dabiri, and B Mittal, and M A Kowalski, and J G Haddad, and J W Sanger
February 1996, Experimental cell research,
J M Sanger, and G Dabiri, and B Mittal, and M A Kowalski, and J G Haddad, and J W Sanger
January 1983, Nature,
J M Sanger, and G Dabiri, and B Mittal, and M A Kowalski, and J G Haddad, and J W Sanger
June 1988, The Journal of cell biology,
J M Sanger, and G Dabiri, and B Mittal, and M A Kowalski, and J G Haddad, and J W Sanger
January 2021, Frontiers in cell and developmental biology,
J M Sanger, and G Dabiri, and B Mittal, and M A Kowalski, and J G Haddad, and J W Sanger
November 1983, FEBS letters,
J M Sanger, and G Dabiri, and B Mittal, and M A Kowalski, and J G Haddad, and J W Sanger
June 1988, The Journal of comparative neurology,
Copied contents to your clipboard!