What happens when calcium binds troponin? What happens when calcium binds troponin? Troponin binds to actin and causes sarcomere
shortening. Troponin changes shape and covers the SR calcium channel, which is a form of negative feedback. Tropomyosin is pulled away from the myosin-binding site on actin. Troponin releases myosin and activates actin.
Tropomyosin is pulled away from the myosin-binding site on actin.
Explanation:
Actin and myosin are contractile proteins present in muscle cells. They interact with each other to cause muscle contraction.
When calcium binds to troponin protein, confirmational changes occur in troponin. It pulls tropomyosin away from myosin binding sites on actin. The sites become free and cross bridge is formed between myosin and actin which leads to muscle contraction. The process continues until no more calcium and ATP is available after which tropomyosin again covers the binding sites on actin.
