Chinmo maintains adult stem cell sex identity by directly regulating Doublesex and Insulin signaling [bulk RNA-seq]

The molecular and cellular signals involved remain unknown. In the adult Drosophila testis, removing the JAK-STAT downstream effector Chinmo from adult somatic cyst stem cells (CySCs) causes their feminization, such that the sex-concordant interactions between male germ cells and the adjacent somatic cells are disrupted, causing gradual formation of testis germ cell tumors (GCT).

Here we use single cell RNA-Seq to characterize cell-type specific transcriptional profiles for chinmo mutant testes undergoing sex transformation. This revealed both expected and novel mutant-specific cell populations and the full repertoire of transcriptomic changes accompanying sex transformation. Cell-cell communication networks were computed among all major cell types, revealing that feminized CySCs have reduced outgoing signaling to themselves and hub cells but elevated outgoing signaling including insulin signaling to germline stem cells (GSCs) /spermatogonia.