Nebulin

Nebulin is a protein that in humans is encoded by the NEB gene. It is a giant protein component of the cytoskeletal structure known as the sarcomere, the basic unit of muscle contraction. Nebulin is crucial for the development and function of skeletal muscle.

Structure

Nebulin is a large, filamentous protein, approximately 600-900 kDa in size. It is composed of approximately 200 repeating modules, each about 35 amino acids in length. These modules are organized into a super-repeat structure, which is thought to bind to actin filaments in the sarcomere.

Function

Nebulin plays a critical role in the regulation of muscle contraction. It is thought to function as a molecular ruler, determining the length of the actin filaments in the sarcomere. Nebulin also interacts with other proteins in the sarcomere, including tropomyosin and troponin, to regulate muscle contraction.

Clinical significance

Mutations in the NEB gene are associated with several types of myopathy, including nemaline myopathy and distal arthrogryposis. These conditions are characterized by muscle weakness and wasting, and can be severe or life-threatening.

Research

Research into the function and structure of nebulin is ongoing. Understanding the role of this protein in muscle contraction and its involvement in disease could lead to new treatments for myopathies and other muscle disorders.

See also

• Nemaline myopathy
• Distal arthrogryposis
• Sarcomere
• Actin
• Tropomyosin
• Troponin