Myosin light chain phosphorylation is correlated with cold-induced changes in platelet shape.
Chilling induces shape changes in platelets from disks to spheres with abundant filopodia. Such changes were time-dependent and correlated well with the phosphorylation of 20-kDa myosin light chain (LC20). Both the shape changes and the phosphorylation were reversible. After the platelets had been chilled, myosin became incorporated into the Triton X-insoluble fraction. When the chilled platelets were immunocytochemically stained, anti-myosin antibody was localized with filamentous structures inside the filopodia. These results suggest that LC20 phosphorylation and subsequent interactions with actin filaments play a crucial role in the cold-induced changes in platelet shape and in the formation of filopodia.
Department of Anatomy, Kyorin University School of Medicine, Mitaka, Tokyo, Japan. kaha@kyorin-u.ac.jp
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H
Kawakami
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Higashihara
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Ohsaka
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Miyazaki
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Ikebe
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Hirano
D001792:Blood Platelets / Q000648:ultrastructure*; D003080:Cold Temperature / Q000009:adverse effects*; D003598:Cytoskeletal Proteins / Q000378:metabolism; D006801:Humans; D016253:Microscopy, Immunoelectron; D018994:Myosin Light Chains / Q000378:metabolism*; D010766:Phosphorylation
D003598:Cytoskeletal Proteins; D018994:Myosin Light Chains