Wenying Qu

To the Editor, Maintaining cellular and organismal homeostasis relies on the dynamic balance between protein synthesis and degradation [1]. In eukaryotic systems, protein degradation is primarily executed through two canonical pathways—the ubiquitin–proteasome system (UPS) and the autophagy–lysosome pathway—which cooperate to preserve proteome integrity by eliminating misfolded, damaged or superfluous proteins [2].

Abstract The ubiquitin-proteasome system (UPS) represents an evolutionarily conserved machinery governing proteostasis through spatiotemporal regulation of protein degradation. While spermatogenesis involves multilayered regulatory mechanisms spanning translation to dynamic post-translational modifications (PTMs), the identity of UPS-associated E3 ligases orchestrating germ cell-specific protein turnover remains elusive.

Conflicts of Interest The authors declare no conflicts of interest. Supporting Information Filename Description ldr5428-sup-0001-supinfo.docxWord 2007 document , 3 MB Data S1. Supporting Information. References , , and . 2018. “Keystone Taxa as Drivers of Microbiome Structure and Functioning.” Nature Reviews. Microbiology 16, no. 9: 567–576. https://doi.org/10.1038/s41579-018-0024-1. , , , et al. 2018.