This gene encodes a ubiquitin-like protein (ubiquilin) that shares a high degree of similarity with related products in yeast, rat and frog. Ubiquilins contain an N-terminal ubiquitin-like domain and a C-terminal ubiquitin-associated domain. They physically associate with both proteasomes and ubiquitin ligases, and are thus thought to functionally link the ubiquitination machinery to the proteasome to affect in vivo protein degradation. This gene is specifically expressed in the testis. It has been suggested that this gene may regulate cell-cycle progression during spermatogenesis, however, it has been shown that the ortholgous mouse gene is dispensable for embryonic development and spermatogenesis. [provided by RefSeq, Nov 2016],TUP-1,UBQLN3,Cell Biology & Developmental Biology,Ubiquitin,UBQLN3