5. How transposon defence shapes ovary development

How does the developing ovary protect itself from harmful transposon activity? Our recent work revealed that excessive expression of gypsy, a retrotransposon with virus-like properties, disrupts ovary development in Drosophila (Liddell et al., 2025, Biology Open; PMID: 41195451).

During pupal development, developing egg chambers form through coordinated interactions between germline and surrounding somatic cells. A specialised group of somatic cells forms the basal stalk, a structure that connects and supports developing egg chambers. We discovered that disrupting the piRNA pathway, which normally suppresses transposon activity, impairs the development of basal stalk precursor cells and consequently prevents proper egg chamber formation.

These findings raise an intriguing possibility: transposon defence may influence ovary development by preventing the formation of egg chambers carrying active retrotransposons.

In this project, we will investigate how gypsy expression interferes with basal stalk development and identify the molecular and genetic pathways responsible. By linking transposon activity to developmental processes, we aim to understand how genome defence mechanisms contribute to the formation of a functional reproductive system.

Techniques: Drosophila genetics, tissue-specific gene manipulation using GAL4/UAS and RNAi, GFP and lacZ reporters, immunohistochemistry, fluorescence microscopy, and RNA sequencing.