Investigation of mechanisms regulating stem cell competition using the Drosophila follicle stem cell model
Developmental Biology
Final Report Abstract
The Drosophila ovary is a widely used model for germ cell and somatic tissue biology. Using single cell RNA-sequencing this project produced an atlas of transcriptomes of every major cell type in the adult ovary as a valuable source for every researcher interested in adult ovarian cell types of the fruit fly. Besides cell type specific gene expression patterns, the atlas can be used to detect stepwise changes in transcriptomes during cellular differentiation and provides information of cell type specific gene regulatory networks. The follicle cell lineage supports germ cell development and serves as a model for epithelial tissue biology. The stem cells in this lineage divide to give rise to transiently amplifying daughter cells, which can replace the stem cell in order to ensure the fitness of the tissue. Whether all daughter cells are competent to replace the stem cell and how heterogeneous this transiently amplifying population of cells is, is poorly understood. By investigating the stepwise changes in transcriptomes in this cell population, this study has provided proof of heterogeneity among the transiently amplifying cells in the follicle cell lineage. The identification of new tools to target a subset of these cells has further led to the discovery that they reach a “point of no return”, at which they are not usually able to replace the stem cell. In addition, the atlas provides proof of several subtypes of escort cells, a population of cells that has mostly been regarded as homogeneous in the past. These cells support early germ cell development and assume niche function for the follicle stem cell, the founder cell of all follicle cells. Using newly identified methods to analyze these subtypes separately from each other, I could show that, while escort cells do not usually produce any other cell types, starvation led to the ability of two escort cell subtypes to convert their fate to follicle stem cells. Together, this project provides a useful resource for researchers interested in the adult Drosophila ovary and has significantly contributed to our understanding of follicle cell and escort cell biology.
Publications
- A single-cell atlas and lineage analysis of the adult Drosophila ovary. Nat. Commun. 11, 5628 (2020)
Rust, K. et al.
(See online at https://doi.org/10.1038/s41467-020-19361-0) - Signal transduction in the early Drosophila follicle stem cell lineage. Current Opinion in Insect Science 37, 39–48 (2020)
Rust, K. & Nystul, T.
(See online at https://doi.org/10.1016/j.cois.2019.11.005)
