Molecular chaperone αb-crystallin regulates the dynamic stability of focal adhesion under mechanical stress conditions

Resilience to stretch stress is an important characteristic that helps maintain cell adhesion and consequently, human health. This study aimed to elucidate the underlying mechanism of adaptation to stretch stress regulated by the molecular chaperone αB-crystallin. Three rat myoblast L6 cell lines, wild type (L6-WT), αB-crystallin knock down (L6-KD), and αB-crystallin overexpressing (L6-OE) cells were used. Muscle cells are less motile because they are specialized for contraction. Forced stretch stress was given to the three cell lines on a soft adhesive sheet, and we found that L6-OE cells showed the highest resilience to stretch stress and the least motility compared to other cell lines. Conversely, L6-KD cells showed the least resilience to stretch stress. Vinculin staining showed that total focal adhesion (FA) size and area of L6-OE cells were significantly larger than those of other cell types. Thus αB-crystallin in myoblast cells contributes the resilience of FA stability during stretch stress.