Mammals, including humans, have very limited regeneration capacity of tissues and organs. Even tissues with a simple structure, like tendon mainly consisting of bundles of collagen fibres, end up with scar tissue formation once injured, which possess significantly lower strength compared to healthy tendons. Surprisingly, we have recently discovered that tendon in newt can regenerate its structure and functions completely following a complete transection (doi.org/10.1002/jor.25705); a loose collagenous tissue firstly connects tendon stubs and gradually regain the structure and functions of normal tendons. Therefore, in this project, we aimed to clarify how mechanical environment generated by ECM components of regenerated tendon regulate the functions of cells within the tissue toward complete regeneration. With our original experimental tendon transection model using Iberian ribbed newts, we will investigate 1) how the alteration of extrinsic mechanical loading affect tendon regeneration, 2) what types of mechanical signals cells within regenerated tissue receive from tissue ECM components during regeneration process, and 3) how these cells generate apply mechanical force to the ECM of regenerated tendon.