The expression of Catsup in escort cells affects Drosophila ovarian stem cell niche establishment and germline stem cells self-renewal via Notch signaling

Stem cell niche provides extrinsic signals to maintain stem cell renewal or initiate cell differentiation. Drosophila niche is composed of somatic terminal filament cells, cap cells and escort cells. However, the underlying mechanism for the development of stem cell niche remains largely unclear. Here we found that the expression of a zinc transporter Catsup is essential for ovary morphogenesis. Catsup knockdown in escort cells results in defects of niche establishment and germline stem cells self-renewal. These defects could be modified by altered expression of genes involved in zinc metabolism or intervention of dietary zinc levels. Further studies indicated that Catsup RNAi affected adult ovary morphogenesis by suppressing Notch signaling. Lastly, we demonstrated that the defects of Catsup RNAi could be restored by overexpression of heat shock cognate protein 70 (Hsc70). These findings expand our understanding of the mechanisms controlling adult oogenesis and niche establishment in Drosophila.(c) 2022 Elsevier Inc. All rights reserved.

Automated summary

This study reveals the crucial role of the zinc transporter Catsup in ovary morphogenesis, as knockdown of Catsup in escort cells leads to defects in niche establishment and germline stem cell self-renewal. Further investigations demonstrate that Catsup affects adult ovary formation by suppressing Notch signaling, and the defects caused by Catsup knockdown can be restored by overexpressing heat shock cognate protein 70 (Hsc70).