Myosin-2

Myosin-2 is a protein that in humans is encoded by the MYH2 gene. It is a member of the myosin superfamily, a group of motor proteins that are essential for muscle contraction and a wide range of other cellular processes.

Structure

Myosin-2 is a hexameric protein composed of two heavy chains and four light chains. The heavy chains have a molecular weight of approximately 200,000 Daltons each, while the light chains have a molecular weight of approximately 20,000 Daltons each. The heavy chains form a coiled-coil structure that is responsible for the protein's motor activity, while the light chains regulate this activity.

Function

Myosin-2 is a motor protein that converts chemical energy in the form of adenosine triphosphate (ATP) into mechanical work. It does this by binding to actin filaments and undergoing a conformational change that results in the movement of the actin filament relative to the myosin-2 molecule. This movement is the basis for muscle contraction and many other cellular processes.

Clinical significance

Mutations in the MYH2 gene can lead to a variety of muscle disorders, including congenital myopathy and myosin storage myopathy. These disorders are characterized by muscle weakness and wasting, and can be life-threatening in severe cases.

See also

• Myosin
• Motor protein
• Muscle contraction
• Congenital myopathy
• Myosin storage myopathy