Developmental Biochemistry, University Medical Center Goettingen, Goettingen, Germany.
Hematology and Oncology, University Medical Center Goettingen, Goettingen, Germany.
Handb Exp Pharmacol. 2021;269:29-43. doi: 10.1007/164_2021_531.
WNT signaling is a key developmental pathway in tissue organization. A recent focus of research is the secretion of WNT proteins from source cells. Research over the past decade on how WNTs are produced and released into the extracellular space has unravelled very specific control mechanisms in the early secretory pathway, specialized trafficking routes, and redundant forms of packaging for delivery to target cells. In this review I discuss the findings that WNT proteins have been found on extracellular vesicles (EVs) such as exosomes and possible functional implications. There is an ongoing debate in the WNT signaling field whether EV are relevant in vivo and can fulfill specific functions, also fueled by the general preconception of EV secretion as cellular garbage disposal. As part of the EV research community, I want to give an overview of what we know and don't know about WNT secretion on EVs and offer a more unifying model that can explain current discrepancies in observations regarding WNT secretion.
WNT 信号通路是组织发育的关键途径。最近的研究重点是 WNT 蛋白从源细胞分泌。在过去十年中，关于 WNT 如何产生并释放到细胞外空间的研究揭示了早期分泌途径、专门的运输途径和用于递送到靶细胞的冗余包装形式中的非常特定的控制机制。在这篇综述中，我讨论了 WNT 蛋白在外泌体等细胞外囊泡 (EV) 上的发现及其可能的功能意义。WNT 信号领域正在争论 EV 是否与体内相关，并且是否可以发挥特定功能，这也受到 EV 分泌被普遍认为是细胞废物处理的先入为主观念的推动。作为 EV 研究界的一员，我想概述一下我们对外泌体上 WNT 分泌的了解和未知，并提供一个更具统一性的模型，以解释目前关于 WNT 分泌的观察结果中的差异。
