This domain is found in Ubiquitin-associated protein 1 (UBAP-1) and similar proteins predominantly found in animals. UBAP-1 is involved in vesicular trafficking process, as it's a component of an endosome- specific endosomal sorting complex I (ESCRT-I). It is thought to play an important role in the ubiquitin pathway and cell progression. It co-localizes with TDP-43 proteins in neuronal cytoplasmic inclusions and acts as a genetic risk factor for frontotemporal lobar degeneration (FTLD). This protein contains an N-terminal UBAP-1-MVB12-associated (UMA) domain, and several tandem ubiquitin- associated (UBA) domains that may be responsible for the binding of ubiquitin-conjugating enzymes. This entry corresponds to UBA2 domain.

1: The UBAP1 subunit of ESCRT-I interacts with ubiquitin via a SOUBA domain. Agromayor M, Soler N, Caballe A, Kueck T, Freund SM, Allen MD, Bycroft M, Perisic O, Ye Y, McDonald B, Scheel H, Hofmann K, Neil SJ, Martin-Serrano J, Williams RL; Structure. 2012;20:414-428. PMID:22405001

2: BuD, a helix-loop-helix DNA-binding domain for genome modification. Stella S, Molina R, Lopez-Mendez B, Juillerat A, Bertonati C, Daboussi F, Campos-Olivas R, Duchateau P, Montoya G; Acta Crystallogr D Biol Crystallogr. 2014;70:2042-2052. PMID:25004980