Abstract
Lysosome activity regulates germline development in multiple species. In the Drosophila testis, lysosomes activate as germ cells exit mitosis and enter meiosis. Notably, reduced activity of germ-cell lysosomes, which is seen during aging, leads to fewer viable sperm. Here, we investigated the activity of Mitf/TFEB, a master regulator of lysosome biogenesis, during Drosophila spermatogenesis. We discovered that Mitf activity was upregulated in meiotic-stage spermatocytes, consistent with the lysosome-activation pattern. However, Mitf activity in spermatocytes declined in older males, concurrent with reduced expression of a Mitf-targeted V-ATPase component. These findings provide insight into the regulation of upstream lysosome controls during spermatogenesis.