Protocol to study the contribution of tendon lineage in the development of mouse temporomandibular joint condylar cartilage using 3D visualization.

Tendon cells have been shown to play a critical role during the postnatal growth of the temporomandibular joint (TMJ) condyle by transdifferentiating into chondrocytes. Here, we present a protocol for tracking the tendon lineage of Scx(CreERT2); R26R(tdTomato); 2.3Col1a1-GFP mice in vivo. We describe steps for sample preparation, tissue clearing, confocal microscopy, and artificial intelligence-based analysis, which are also applicable to other mineralized tissues. This protocol enables the study of the contribution of tendon cells to condylar chondrogenesis through 3D visualization. For complete details on the use and execution of this protocol, please refer to Yi et al.(1).