Department of Human Genetics, David Geffen School of Medicine, University of California-Los Angeles, CA 90095, USA.
Dev Dyn. 2012 Nov;241(11):1782-98. doi: 10.1002/dvdy.23870. Epub 2012 Oct 5.
Mechanisms involved in early patterning of the mammalian gonad as it develops from a bipotential state into a testis or an ovary are as yet not well understood. Sex-specific vascularization is essential in this process, but more specific mechanisms required to, for example, establish interstitial vs. cord compartments in the testis or ovigerous cords in the ovary have not been reported. Adherens junctions (AJs) are known for their roles in morphogenesis; we, therefore, examined expression of AJ components including β-catenin, p120 catenin, and cadherins for possible involvement in sex-specific patterning of the gonad.
We show that, at the time of early gonadal sex differentiation, membrane-associated β-catenin and p120 catenin colocalize with cell-specific cadherins in both sex-nonspecific and sex-specific patterns. These expression patterns are consistent with an influence of AJs in overall patterning of the testis vs. ovary through known AJ mechanisms of cell-cell adhesion, cell sorting, and boundary formation.
Together these complex and dynamic patterns of AJ component expression precisely mirror patterning of tissues during gonadogenesis and raise the possibility that AJs are essential effectors of patterning within the developing testis and ovary.
哺乳动物性腺从双潜能状态发育为睾丸或卵巢的早期模式形成的机制尚不清楚。在这个过程中，性别的特异性血管化是必不可少的，但还没有报道更具体的机制，例如在睾丸中建立间质与索状结构之间的区别，或者在卵巢中建立产卵管。黏附连接（AJs）以其在形态发生中的作用而闻名；因此，我们检查了 AJ 成分的表达，包括β-连环蛋白、p120 连环蛋白和钙黏蛋白，以研究它们是否可能参与性腺的性别特异性模式形成。
我们发现，在早期性腺性别分化时，膜相关的β-连环蛋白和 p120 连环蛋白与细胞特异性钙黏蛋白以非性别特异性和性别特异性的模式共定位。这些表达模式与 AJ 通过细胞-细胞黏附、细胞分选和边界形成等已知的 AJ 机制，对睾丸和卵巢整体模式形成的影响一致。
这些 AJ 成分表达的复杂和动态模式与性腺发生过程中组织的模式形成精确对应，并提出了 AJ 可能是发育中的睾丸和卵巢内模式形成的必要效应器的可能性。
