Investigating the Role of the Histone Demethylase Lid in the Drosophila Testis Niche

Histone modification enzymes are highly expressed in the Drosophila melanogaster male germline stem cell niche. One of these modifiers, little imaginal discs (Lid), is a histone demethylase that specifically targets the H3K4me3 mark. Whereas studies have shown that activation of the Janus kinase signal transducer and activator of transcription (JAK-STAT) signaling pathway in cyst stem cells is crucial for proliferation and maintenance of germline stem cells (GSCs), the function of Stat92E in germ cells is believed to only regulate GSC-hub adhesion through DE-Cadherin. Here we show that Lid functions to regulate Stat92E, the downstream transcription factor for the JAK-STAT signaling pathway, in Drosophila male germ cells. Our results reveal that Lid is a positive regulator of Stat92E in germ cells through a derepression mechanism: Lid represses Ptp61F’s inhibitive effect on Stat92E. Loss of lid in germ cells results in a decrease in the number of GSCs. Our data suggest that activation of the JAK-STAT signaling pathway in germ cells is required for proper GSC proliferation and maintenance. Therefore, our study provides new insights into the functions of the JAK-STAT signaling pathway in the Drosophila male GSC niche, specifically in germ cells, as well as helps to better understand the biological role of histone demethylase in vivo

Targeting CD133 improves chemotherapeutic efficacy of recurrent pediatric pilocytic astrocytoma following prolonged chemotherapy

Quantification of western blot results showing overexpression of pAKT(S473, T308) and pNF-ƙB/p65 in recurrent PAs with chemotherapy, compared to matched primary tumors. (TIF 52 kb