ABSTRACT
Clearance of dying cells is essential for tissue homeostasis and requires both professional and non-professional phagocytes; however, it is unclear what promotes phagocytosis by non-professional phagocytes. Follicle cells of Drosophila egg chambers function as non-professional phagocytes to clear large germ cell debris in mid and late oogenesis, providing an excellent model for the study of non-professional phagocytes. Here, we demonstrate that GATA factor Serpent (Srp) plays an indispensable role in promoting the phagocytic capacity of follicle cells in both processes. Srp is upregulated in follicle cells of degenerating mid-stage egg chambers, and its knockdown results in incomplete clearance of germ cell debris and premature follicle cell death. In addition, Srp is upregulated in stretch follicle cells and is essential for clearing the nurse cell nuclei in late oogenesis. Genetic analysis reveals that Srp acts downstream of JNK signaling to upregulate the expression of the phagocytic receptor Draper as well as other components in the corpse processing machinery. Our findings highlight the crucial role for Srp in non-professional phagocytes during Drosophila oogenesis, which may also be conserved across species.
Footnotes
Author contributions
Conceptualization: B.Z., J.S.; Data curation: B.Z., H.G., J.S.; Formal analysis: B.Z., J.S.; Funding acquisition: J.S.; Investigation: B.Z., J.S.; Methodology: B.Z., H.G.; Project administration: J.S.; Resources: J.S.; Validation: B.Z.; Visualization: B.Z.; Writing – original draft: B.Z., J.S.; Writing – review & editing: B.Z., H.G., J.S.
Funding
H.G. is supported by the University of Connecticut IDEA Grant program. J.S. is supported by the University of Connecticut Start-Up Fund, and the Eunice Kennedy Shriver National Institute of Child Health and Human Development (R01-HD086175 and R01-HD097206). Deposited in PMC for release after 12 months.
Data and resource availability
All relevant data can be found within the article and its supplementary information.
The people behind the papers
This article has an associated ‘The people behind the papers’ interview with some of the authors.
![Development logo - Browse by subject: Explore Development's content, now easily accessible by subject area. The ad has a black background with three vibrant scientific images: a developing embryo on the left, a green plant-like structure in the center, and a gastruloid (a circular cell with a bright pink center and blue outer ring) on the right. [Blue button: browse content].](https://cob.silverchair-cdn.com/ImageLibrary/Development/Snippets/2025_05_Dev_Browse-by-subject_600x230_Snippet.png?versionId=8863)
