Titin plays an important role in eccentric contraction by creating elastic property in the sarcomere. It can restore muscle to its rest length by stretching and increasing its length. Titin’s structure is made of 244 domains. Due to its position, the I10 domain can be subjected to a mutation which leads to Arrhythmogenic cardiomyopathy. Furthermore, the calcium ion has an important role in muscle contractions by binding to some domains like I10 in titin and accordingly creating changes in the unfolding force of these domains. The purpose of this study was to investigate the effect of calcium binding on the unfolding force of the I10 domain for the normal and mutated states. For this reason, the steered molecular dynamics simulation was performed in different states with various pulling rates. According to the results, calcium binding leads to a rising in the unfolding force of the I10 domain. In addition, mutation decreases the unfolding force of the domain, but the presence of calcium compensates for this effect by raising the unfolding force. Results also indicate that by increasing the pulling rates, the unfolding force would increase considerably.

Titin 通过在肌节中产生弹性特性，在离心收缩中起重要作用。它可以通过拉伸和增加肌肉长度将肌肉恢复到静止长度。Titin 的结构由 244 个结构域组成。由于其位置，I10 结构域可能会发生突变，从而导致致心律失常性心肌病。此外，钙离子通过与肌动蛋白中的 I10 等结构域结合，从而在这些结构域的展开力中产生变化，从而在肌肉收缩中发挥重要作用。本研究的目的是研究钙结合对正常和突变状态下 I10 结构域展开力的影响。出于这个原因，转向分子动力学模拟是在不同状态下以不同的拉动速率进行的。根据结果​​，钙结合导致 I10 域的展开力上升。此外，突变降低了结构域的展开力，但钙的存在通过提高展开力来补偿这种效应。结果还表明，通过增加拉动速率，展开力将显着增加。