TY - JOUR T1 - Measuring Mechanodynamics using an Unsupported Epithelial Monolayer Grown at an Air-Water Interface JF - bioRxiv DO - 10.1101/052555 SP - 052555 AU - Corinne Gullekson AU - Matthew Walker AU - James L. Harden AU - Andrew E. Pelling Y1 - 2016/01/01 UR - http://biorxiv.org/content/early/2016/05/13/052555.abstract N2 - Actomyosin contraction and relaxation in a monolayer is a fundamental biophysical process in development and homeostasis. Current methods used to characterize the mechanodynamics of monolayers often involve cells grown on solid supports such as glass or gels. The results of these studies are fundamentally influenced by these supporting structures. Here, we describe a new methodology for measuring the mechanodynamics of epithelial monolayers by culturing cells at an air-liquid interface. These model monolayers are grown in the absence of any supporting structures removing cell-substrate effects. This method’s potential was evaluated by observing and quantifying the generation and release of internal stresses upon actomyosin contraction (320±50Pa) and relaxation (190±40Pa) in response to chemical treatments. Although unsupported monolayers exhibited clear major and minor strain axes, they were not correlated to nuclear alignment as observed when the monolayers were grown on soft deformable gels. It was also observed that both gels and glass substrates led to the promotion of long-range cell nuclei alignment not seen in the hanging drop model. This new approach provides us with a picture of basal actomyosin mechanodynamics in a simplified system allowing us to infer how the presence of a substrate impacts contractility and long-range multi-cellular organization and dynamics. ER -