UBA domain found in ubiquitin-associated and SH3 domain-containing protein A (UBS3A) and similar proteins
UBS3A, also called Cbl-interacting protein 4 (CLIP4), suppressor of T-cell receptor signaling 2 (Sts-2), or T-cell ubiquitin ligand 1 (TULA-1), is a lymphoid protein only detected in thymus, spleen, and bone marrow. UBS3A exhibits extremely low phosphatase activity, but is capable of promoting T-cell apoptosis independent of either T cell receptor (TCR)/CD3-mediated signaling or caspase activity. It functions as a negative regulator of TCR signaling. UBS3A can also inhibit HIV-1 biogenesis through the binding of ATP-binding cassette protein family E member 1 (ABCE-1), a host factor of HIV-1 assembly. Moreover, UBS3A acts as the Cbl- and ubiquitin-interacting protein that can inhibit endocytosis and downregulation of ligand-activated epidermal growth factor receptor (EGFR) by impairing Cbl-induced ubiquitination, as well as inhibit clathrin-dependent endocytosis in general. This family also includes Arabidopsis thaliana ubiquitin carboxyl-terminal hydrolase 14 (atUBP14) and some uncharacterized AAA-type ATPase-like proteins found in plants.
Jiyao W et al.(2023). "The conserved domain database in 2023.",