Interaction between calponin and smooth muscle myosin

FEBS Letters

Szymanski, Pawel T.¹  Tao, Terence¹ 

[1] Department of Muscle Research, Boston Biomedical Research Institute, 20 Staniford Street, Boston, MA 02114, USA

关键词: Calponin;    Myosin;    Smooth muscle;    CaM;    calmodulin;    DTT;    Dithiothreitol;    EGTA;    [ethylenebis(oxyethylenentrilo)tetraacetic;    GCan;    gizzard calponin;    RαCaN;    recombinant α-isoform of calponin;    Tn-C;    troponin-C;    SDS-PAGE;    sodium dodecyl sulfate polyacrylamide gel electrophosis;   

DOI  :  10.1016/0014-5793(93)80348-X

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Calponin is a thin filament-associated protein in smooth muscle that has been shown to bind actin, tropomyosin and calmodulin, and has been implicated to play a role in regulation of smooth muscle contractility. Using a centrifugation assay we found that calponin interacts with unphosphorylated filamentous smooth muscle myosin. We found that this calponin-myosin interaction is reversed by Ca²⁺-CaM, and depends on ionic strength. At 50 mM NaCI the binding constant and the stoichiometry of this interaction were estimated to be 2 × 10⁶ M⁻¹, and 1.2–2.4 calponin per myosin, respectively. We suggest that the calponin-myosin interaction could be involved in regulation of smooth muscle contractility by anchoring myosin to actin.

【 授权许可】

Unknown