Definition of actin in English:



mass nounBiochemistry
  • A protein which forms (together with myosin) the contractile filaments of muscle cells, and is also involved in motion in other types of cell.

    • ‘Muscle contraction is dependent on two proteins, actin and myosin.’
    • ‘As the cells round up, actin and myosin moieties are being redistributed underneath the plasma membrane.’
    • ‘Rabbit skeletal muscle actin was prepared as described and subjected to gel filtration.’
    • ‘Muscle contraction results from the cyclic interaction of the myosin head with actin.’
    • ‘Striated muscle contraction is regulated by a protein complex bound to actin.’
    put on, present, produce, give
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1940: from Greek aktis, aktin- ‘ray’ + -in.