What is the main component of the thin filaments in muscle fibers and is responsible for muscle contraction?

Actin Protein

Explanation:

Protein named “Actin” is the main component of thin filament in muscles. There are some other proteins such as troponin and tropomyosin that forms the thin filament.  However, actin plays an important role in the contraction of muscles as each actin molecule consists of single myosin binding site. All actin molecules join together to form a chain twisted into helix configuration which is very essential for the contraction mechanism in muscles.

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