# Meiotic activation of Mitf/TFEB declines with age in the Drosophila testis

## TL;DR

This study shows that lysosome activity in fruit fly testes declines with age, affecting sperm viability.

## Contribution

The paper reveals that Mitf/TFEB activity during meiosis decreases with age in Drosophila testes.

## Key findings

- Mitf/TFEB activity increases in meiotic-stage spermatocytes.
- Mitf activity declines in older males, linked to reduced V-ATPase expression.
- Lysosome activation patterns are connected to Mitf regulation during spermatogenesis.

## 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.