Department of Biochemistry, Graduate School of Medicine, Osaka University, Osaka, Japan.
Int Rev Cell Mol Biol. 2011;291:21-71. doi: 10.1016/B978-0-12-386035-4.00002-1.
Wnts compromise a large family of secreted, hydrophobic glycoproteins that control a variety of developmental and adult processes in all metazoan organisms. Recent advances in the Wnt-signal studies have revealed that distinct Wnts activate multiple intracellular cascades that regulate cellular proliferation, differentiation, migration, and polarity. Although the mechanism by which Wnts regulate different pathways selectively remains to be clarified, evidence has accumulated that in addition to the formation of ligand-receptor pairs, phosphorylation of receptors, receptor-mediated endocytosis, acidification, and the presence of cofactors, such as heparan sulfate proteoglycans, are also involved in the activation of specific Wnt pathways. Here, we review the mechanism of activation in Wnt signaling initiated on the cell-surface membrane. In addition, the mechanisms for fine-tuning by cross talk between Wnt and other signaling are also discussed.
Wnts 是一类庞大的分泌型疏水性糖蛋白家族，在所有后生动物中控制着多种发育和成年过程。最近对 Wnt 信号的研究进展揭示，不同的 Wnts 激活多种细胞内级联反应，调节细胞增殖、分化、迁移和极性。尽管 Wnts 选择性调节不同途径的机制尚待阐明，但有证据表明，除了配体-受体对的形成、受体磷酸化、受体介导的内吞作用、酸化以及硫酸乙酰肝素蛋白聚糖等辅助因子的存在外，特定 Wnt 途径的激活也涉及其中。在这里，我们综述了在细胞膜表面起始的 Wnt 信号转导的激活机制。此外，还讨论了 Wnt 与其他信号通路之间的相互作用对信号通路精细调控的机制。
