Title

The tip of the coiled-coil rod determines the filament formation of smooth muscle and nonmuscle myosin

UMMS Affiliation

Departments of Physiology and Cell Biology

Date

6-8-2001

Document Type

Article

Subjects

Actins; Animals; Antibodies, Monoclonal; Binding Sites; Blotting, Western; COS Cells; Cell Division; DNA, Complementary; Electrophoresis, Polyacrylamide Gel; Green Fluorescent Proteins; Interphase; Luminescent Proteins; Microscopy, Confocal; Microscopy, Electron; Microscopy, Fluorescence; Models, Biological; Muscle, Smooth; Mutation; Myosins; Protein Binding; Protein Structure, Tertiary; Rabbits; Recombinant Fusion Proteins; Transfection; Turkey

Disciplines

Life Sciences | Medicine and Health Sciences

Abstract

Myosin II self-assembles to form thick filaments that are attributed to its long coiled-coil tail domain. The present study has determined a region critical for filament formation of vertebrate smooth muscle and nonmuscle myosin II. A monoclonal antibody recognizing the 28 residues from the C-terminal end of the coiled-coil domain of smooth muscle myosin II completely inhibited filament formation, whereas other antibodies recognizing other parts of the coiled-coil did not. To determine the importance of this region in the filament assembly in vivo, green fluorescent protein (GFP)-tagged smooth muscle myosin was expressed in COS-7 cells, and the filamentous localization of the GFP signal was monitored by fluorescence microscopy. Wild type GFP-tagged smooth muscle myosin colocalized with F-actin during interphase and was also recruited into the contractile ring during cytokinesis. Myosin with the nonhelical tail piece deleted showed similar behavior, whereas deletion of the 28 residues at the C-terminal end of the coiled-coil domain abolished this localization. Deletion of the corresponding region of GFP-tagged nonmuscle myosin IIA also abolished this localization. We conclude that the C-terminal end of the coiled-coil domain, but not the nonhelical tail piece, of myosin II is critical for myosin filament formation both in vitro and in vivo.

Rights and Permissions

Citation: J Biol Chem. 2001 Aug 10;276(32):30293-300. Epub 2001 Jun 6. Link to article on publisher's site

DOI of Published Version

10.1074/jbc.M101969200

Related Resources

Link to Article in PubMed

Journal Title

The Journal of biological chemistry

PubMed ID

11395487