Division of Biomedical Sciences, Center for Craniofacial Molecular Biology, Ostrow School of Dentistry, University of Southern California, Los Angeles, CA 90033, USA.
Department of Biochemistry and Molecular Medicine, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA.
Development. 2021 Apr 15;148(8). doi: 10.1242/dev.186916. Epub 2021 Apr 16.
Tendons and ligaments are fibrous connective tissues vital to the transmission of force and stabilization of the musculoskeletal system. Arising in precise regions of the embryo, tendons and ligaments share many properties and little is known about the molecular differences that differentiate them. Recent studies have revealed heterogeneity and plasticity within tendon and ligament cells, raising questions regarding the developmental mechanisms regulating tendon and ligament identity. Here, we discuss recent findings that contribute to our understanding of the mechanisms that establish and maintain tendon progenitors and their differentiated progeny in the head, trunk and limb. We also review the extent to which these findings are specific to certain anatomical regions and model organisms, and indicate which findings similarly apply to ligaments. Finally, we address current research regarding the cellular lineages that contribute to tendon and ligament repair, and to what extent their regulation is conserved within tendon and ligament development.
肌腱和韧带是纤维结缔组织，对于力的传递和骨骼肌肉系统的稳定至关重要。肌腱和韧带起源于胚胎的特定区域，它们具有许多共同的特性，而对于区分它们的分子差异知之甚少。最近的研究揭示了肌腱和韧带细胞内的异质性和可塑性，这引发了关于调节肌腱和韧带特性的发育机制的问题。在这里，我们讨论了最近的发现，这些发现有助于我们理解在头部、躯干和四肢中建立和维持肌腱祖细胞及其分化后代的机制。我们还回顾了这些发现在多大程度上特定于某些解剖区域和模式生物，并指出哪些发现同样适用于韧带。最后，我们讨论了目前关于有助于肌腱和韧带修复的细胞谱系的研究，以及它们在多大程度上在肌腱和韧带发育中受到保守调控。
