UBASH3A (ubiquitin-associated and SH3 domain-containing protein A, also known as STS-2 or TULA) belongs to the TULA family. It is only found in lymphoid cells and exhibits weak phosphatase activity [, ]. UBASH3A facilitates T cell-induced apoptosis through interaction with the apoptosis-inducing factor AIF []. It is involved in regulating the level of phosphorylation of the zeta-associated protein (ZAP)-70 tyrosine kinase [].This entry represents the SH3 domain of UBASH3A. The TULA family includes two members termed p70/STS-1/TULA-2 and UBASH3A/STS-2/TULA/Cbl-InteractingProtein 4 (CLIP4). TULA proteins contain an N-terminal UBA domain, a central SH3 domain, and a C-terminal histidine phosphatase domain. They bind c-Cbl (a multidomain adaptor and an E3 ubiquitinligase) through the SH3 domain []and to ubiquitin via UBA [].
