Deshpande Girish, Nouri Ali, Schedl Paul
Department of Molecular Biology, Princeton University, Princeton, New Jersey 08540
Department of Molecular Biology, Princeton University, Princeton, New Jersey 08540.
Genetics. 2016 Feb;202(2):661-73. doi: 10.1534/genetics.115.177857. Epub 2015 Nov 27.
The embryonic gonad of Drosophila melanogaster begins to display sexually dimorphic traits soon after its formation. Here we demonstrate the involvement of a wnt family ligand, wnt-2, in the induction of these sex-specific differences. We show that wnt-2 contributes to the survival of a male-specific population of somatic gonadal precursor cells (SGPs), the male-specific SGPs that are located at the posterior of the male gonad. We also show that the Wnt-2 ligand synergizes with the JAK-STAT ligand Upd, which is produced by SGPs at the anterior of the gonad to activate the STAT pathway in male germ cells. We suggest that the use of two spatially separated signaling systems to initiate the JAK-STAT stem cell maintenance pathway in germ cells provides a mechanism for increasing the pool of potential progenitors of the germline stem cells in the adult testes. Finally, we present evidence indicating that, like the JAK-STAT pathway, wnt-2 stimulates germ cells in male embryos to re-enter the cell cycle.
黑腹果蝇的胚胎性腺在形成后不久就开始表现出性别二态性特征。在此，我们证明了Wnt家族配体Wnt-2参与了这些性别特异性差异的诱导过程。我们发现，Wnt-2有助于位于雄性性腺后部的雄性特异性体细胞性腺前体细胞（SGP）群体的存活。我们还表明，Wnt-2配体与性腺前部的SGP产生的JAK-STAT配体Upd协同作用，以激活雄性生殖细胞中的STAT途径。我们认为，利用两个空间上分离的信号系统来启动生殖细胞中的JAK-STAT干细胞维持途径，为增加成年睾丸中生殖系干细胞潜在祖细胞的数量提供了一种机制。最后，我们提供的证据表明，与JAK-STAT途径一样，Wnt-2刺激雄性胚胎中的生殖细胞重新进入细胞周期。
