Katagade Vrushali, Kandroo Manisha, Ratnaparkhi Anuradha
MACS-Agharkar Research Institute (Affiliated to Savitribai Phule Pune University), Developmental Biology Group, G.G. Agarkar Road, Pune 411 004, Maharashtra, India.
G3 (Bethesda). 2024 May 7;14(5). doi: 10.1093/g3journal/jkae032.
In Drosophila, the signaling pathway activated by the ligand Folded gastrulation (Fog) is among the few known G protein-coupled receptor (GPCR) pathways to regulate cell shape change with a well-characterized role in gastrulation. However, an understanding of the spectrum of morphogenetic events regulated by Fog signaling is still lacking. Here, we present an analysis of the expression pattern and regulation of fog using a genome-engineered Fog::sfGFP line. We show that Fog expression is widespread and in tissues previously not associated with the signaling pathway including germ cells, trachea, and amnioserosa. In the central nervous system (CNS), we find that the ligand is expressed in multiple types of glia indicating a prominent role in the development of these cells. Consistent with this, we have identified 3 intronic enhancers whose expression in the CNS overlaps with Fog::sfGFP. Further, we show that enhancer-1, (fogintenh-1) located proximal to the coding exon is responsive to AbdA. Supporting this, we find that fog expression is downregulated in abdA mutants. Together, our study highlights the broad scope of Fog-GPCR signaling during embryogenesis and identifies Hox gene AbdA as a novel regulator of fog expression.
在果蝇中，由配体折叠原肠胚形成因子（Fog）激活的信号通路是少数已知的G蛋白偶联受体（GPCR）信号通路之一，在原肠胚形成过程中具有明确的调节细胞形状变化的作用。然而，目前仍缺乏对Fog信号通路所调节的形态发生事件范围的了解。在此，我们利用基因组工程构建的Fog::sfGFP品系，对fog的表达模式和调控进行了分析。我们发现Fog的表达广泛存在于包括生殖细胞、气管和羊膜浆膜等先前未与该信号通路相关联的组织中。在中枢神经系统（CNS）中，我们发现该配体在多种类型的神经胶质细胞中表达，表明其在这些细胞的发育中具有重要作用。与此一致的是，我们鉴定出3个内含子增强子，它们在中枢神经系统中的表达与Fog::sfGFP重叠。此外，我们表明位于编码外显子近端的增强子1（fogintenh-1）对AbdA有反应。支持这一点的是，我们发现fog在abdA突变体中的表达下调。总之，我们的研究突出了胚胎发育过程中Fog-GPCR信号通路的广泛作用，并确定Hox基因AbdA是fog表达的一种新型调节因子。
