USP8 is associated with
endosomal trafficking, it is not clear that this isopeptidase is involved in
the commitment to lysosomal sorting. Additional research has shown that USP8
plays a critical role in the stability of receptor tyrosine kinases. USP8 has
been demonstrated to regulate the stability of Nrdp1, a E3 ubiquitin ligase. Among USP8’s many functions it has been shown to be involved in mitophagy—a regulation step vital for neuronal health and longevity—as well as having selectivity for K63 and K48 ubiquitin chains.