TY - JOUR TI - Reciprocal interaction between mesenchymal stem cells and transit amplifying cells regulates tissue homeostasis AU - Jing, Junjun AU - Feng, Jifan AU - Li, Jingyuan AU - Zhao, Hu AU - Ho, Thach-Vu AU - He, Jinzhi AU - Yuan, Yuan AU - Guo, Tingwei AU - Du, Jiahui AU - Urata, Mark AU - Sharpe, Paul AU - Chai, Yang A2 - Wellik, Deneen A2 - Cheah, Kathryn Song Eng A2 - Wellik, Deneen VL - 10 PY - 2021 DA - 2021/01/22 SP - e59459 C1 - eLife 2021;10:e59459 DO - 10.7554/eLife.59459 UR - https://doi.org/10.7554/eLife.59459 AB - Interaction between adult stem cells and their progeny is critical for tissue homeostasis and regeneration. In multiple organs, mesenchymal stem cells (MSCs) give rise to transit amplifying cells (TACs), which then differentiate into different cell types. However, whether and how MSCs interact with TACs remains unknown. Using the adult mouse incisor as a model, we present in vivo evidence that TACs and MSCs have distinct genetic programs and engage in reciprocal signaling cross talk to maintain tissue homeostasis. Specifically, an IGF-WNT signaling cascade is involved in the feedforward from MSCs to TACs. TACs are regulated by tissue-autonomous canonical WNT signaling and can feedback to MSCs and regulate MSC maintenance via Wnt5a/Ror2-mediated non-canonical WNT signaling. Collectively, these findings highlight the importance of coordinated bidirectional signaling interaction between MSCs and TACs in instructing mesenchymal tissue homeostasis, and the mechanisms identified here have important implications for MSC–TAC interaction in other organs. KW - mesenchymal stem cell KW - tissue homeostasis KW - incisor JF - eLife SN - 2050-084X PB - eLife Sciences Publications, Ltd ER -