Molecular cloning, chromosome mapping and characterization of UBQLN3 a testis-specific gene that contains an ubiquitin-like domain

The sequence of the ubiquitin protein is highly conserved between species a nd has facilitated the cloning of numerous ubiquitin-like proteins. In the present study, we report the cloning of the cDNA for human ubiquilin 3 (UBQ LN3). The deduced amino acid sequence of UBQLN3 contains a UBQ domain (ubiq uitin-like) in the amino terminus as well as two highly conserved domains f ound in several recently cloned ubiquitin-like proteins. One of these domai ns, termed the NP domain, is a highly conserved 93 amino acid region presen t in UBQLN3 and several ubiquitin-like proteins. The last conserved domain is the UBA domain (ubiquitin-associated) found in a variety of proteins of the ubiquination pathway. The human UBQLN3 gene was mapped to the 11p15 reg ion of chromosome 11. Northern blot analysis of multiple human and mouse ti ssues demonstrated UBQLN3 mRNA expression specifically in testis. (C) 2000 Elsevier Science B.V. All rights reserved.