UBA domain-like superfamily; The ubiquitin-associated (UBA) domain-like superfamily contains alpha-helical structural homology ubiquitin-binding domains, including UBA domains and coupling of ubiquitin conjugation to endoplasmic reticulum degradation (CUE) domains which share a common three-helical bundle architecture. UBA domains are commonly occurring sequence motifs found in proteins involved in ubiquitin-mediated proteolysis. They contribute to ubiquitin (Ub) binding or ubiquitin-like (UbL) domain binding. However, some kinds of UBA domains can only bind the UbL domain, but not the Ub domain. UBA domains are normally comprised of compact three-helix bundles which contain a conserved GF/Y-loop. They can bind polyubiquitin with high affinity. They also bind monoubiquitin and other proteins. Most UBA domain-containing proteins have one UBA domain, but some harbor two or three UBA domains. CUE domain containing proteins are characterized by an FP and a di-leucine-like sequence and bind to monoubiquitin with varying affinities. Some higher eukaryotic CUE domain proteins do not bind monoubiquitin efficiently, since they carry LP, rather than FP among CUE domains. This superfamily also includes many UBA-like domains found in AMP-activated protein kinase (AMPK) related kinases, the NXF family of mRNA nuclear export factors, elongation factor Ts (EF-Ts), nascent polypeptide-associated complex subunit alpha (NACA) and similar proteins. Although many UBA-like domains may have a conserved TG but not GF/Y-loop, they still show a high level of structural and sequence similarity with three-helical ubiquitin binding domains.

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gi 1034584612   1 MACTQAGERTAIYCLTQNEWRLDEATDSFFQNP 33
Cdd:cd14412    15 MAFTQAGERTAIYCLTQNEWKLEVATDNYFQNP 47

UBA-like domain found in DCN1-like protein 2 (DCNL2) and similar proteins; DCNL2 (defective in cullin neddylation protein 1-like protein 2), also called DCUN1 domain-containing protein 2, is encoded by gene DCUN1D2. Although its biological function remains unclear, DCNL2 shows high sequence similarity with DCNL1, a protein that plays an essential role in the neddylation E3 complex and participates in the release of inhibitory effects of CAND1 on cullin-RING ligase E3 complex assembly and activity. At this point, DCNL2 may also contribute to neddylation of cullin components of SCF-type E3 ubiquitin ligase complexes. Like DCNL1, DCNL2 contains an N-terminal ubiquitin-associated (UBA)-like domain and a C-terminal cullin binding domain that is responsible for the binding to cullins and Rbx-1, components of an E3 ubiquitin ligase complex for neddylation.

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gi 1034584612   1 MACTQAGERTAIYCLTQNEWRLDEATDSFFQNP 33
Cdd:cd14412    15 MAFTQAGERTAIYCLTQNEWKLEVATDNYFQNP 47

UBA-like domain found in DCN1-like protein 2 (DCNL2) and similar proteins; DCNL2 (defective in cullin neddylation protein 1-like protein 2), also called DCUN1 domain-containing protein 2, is encoded by gene DCUN1D2. Although its biological function remains unclear, DCNL2 shows high sequence similarity with DCNL1, a protein that plays an essential role in the neddylation E3 complex and participates in the release of inhibitory effects of CAND1 on cullin-RING ligase E3 complex assembly and activity. At this point, DCNL2 may also contribute to neddylation of cullin components of SCF-type E3 ubiquitin ligase complexes. Like DCNL1, DCNL2 contains an N-terminal ubiquitin-associated (UBA)-like domain and a C-terminal cullin binding domain that is responsible for the binding to cullins and Rbx-1, components of an E3 ubiquitin ligase complex for neddylation.

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gi 1034584612   1 MACTQAGERTAIYCLTQNEWRLDEATDSFFQNP 33
Cdd:cd14412    15 MAFTQAGERTAIYCLTQNEWKLEVATDNYFQNP 47

UBA-like domain found in DCN1-like protein 1 (DCNL1) and similar proteins; DCNL1 (defective in cullin neddylation protein 1-like protein 1), also called DCUN1 domain-containing protein 1, is encoded by squamous cell carcinoma-related oncogene SCCRO (DCUN1D1). It interacts with known cullin isoforms as well as ROC1, Ubc12 and CAND1, the components of the neddylation pathway. It plays an essential role in the neddylation E3 complex and participates in the release of inhibitory effects of CAND1 on cullin-RING ligase E3 complex assembly and activity. DCNL1 contains an N-terminal ubiquitin-associated (UBA)-like domain and a C-terminal cullin binding domain that binds to cullins and Rbx-1, components of an E3 ubiquitin ligase complex for neddylation.

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gi 1034584612   1 MACTQAGERTAIYCLTQNEWRLDEATDSFFQNPD 34
Cdd:cd14411    16 MIFTQSSEKTAVSCLSQNDWKLDVATDNFFQNPE 49