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.

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.

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