UBA domain of eukaryotic protein linking integrin-associated protein (IAP, also known as CD47) with cytoskeleton (PLIC) proteins; The PLIC proteins (or ubiquilins) family contains human homologs of the yeast ubiquitin-like Dsk2 protein, PLIC-1 (also called ubiquilin-1), PLIC-2 (also called ubiquilin-2 or Chap1), PLIC-3 (also called ubiquilin-3) and PLIC-4 (also called ubiquilin-4, Ataxin-1 interacting ubiquitin-like protein, A1Up, Connexin43-interacting protein of 75 kDa, or CIP75), and mouse PLIC proteins. They are ubiquitin-binding adaptor proteins involved in all protein degradation pathways through delivering ubiquitinated substrates to proteasomes. They also promote autophagy-dependent cell survival during nutrient starvation. PLIC-1 regulates the function of the thrombospondin receptor CD47 and G protein signaling. It plays a role in TLR4-mediated signaling through interacting with the Toll/interleukin-1 receptor (TIR) domain of TLR4. It also inhibits the TLR3-Trif antiviral pathway by reducing the abundance of Trif. Moreover, PLIC-1 binds to gamma-aminobutyric acid receptors (GABAARs) and modulates the ubiquitin-dependent, proteasomal degradation of GABAARs. Furthermore, PLIC-1 acts as a molecular chaperone regulating amyloid precursor protein (APP) biosynthesis, trafficking, and degradation by stimulating K63-linked polyubiquitination of lysine 688 in the APP intracellular domain. In addition, PLIC-1 is involved in the protein aggregation-stress pathway via associating with the ubiquitin-interacting motif (UIM) proteins ataxin 3, HSJ1a, and epidermal growth factor substrate 15 (EPS15). PLIC-2 is a protein that binds the ATPase domain of the HSP70-like Stch protein. It functions as a negative regulator of G protein-coupled receptor (GPCR) endocytosis. It also involved in amyotrophic lateral sclerosis (ALS)-related dementia. PLIC-3 is encoded by UBQLN3, a testis-specific gene. It shows high sequence similarity with the Xenopus protein XDRP1, a nuclear phosphoprotein that binds to the N-terminus of cyclin A and inhibits Ca2+-induced degradation of cyclin A, but not cyclin B. PLIC-4 is a ubiquitin-like nuclear protein that interacts with ataxin-1 and further links ataxin-1 with the chaperone and ubiquitin-proteasome pathways. It also binds to the non-ubiquitinated gap junction protein connexin43 (Cx43) and regulates the turnover of Cx43 through the proteasomal pathway. PLIC proteins contain an N-terminal ubiquitin-like (UBL) domain that is responsible for the binding of ubiquitin-interacting motifs (UIMs) expressed by proteasomes and endocytic adaptors, and C-terminal ubiquitin-associated (UBA) domain that interacts with ubiquitin chains present on proteins destined for proteasomal degradation. In addition, mammalian PLIC2 proteins have an extra collagen-like motif region which is absent in other PLIC proteins and the yeast Dsk2 protein.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|
gi 34328236 595 RFQQQLEQLNAMGFLNREANLQALIATGGDINAAIERLLG 634
Cdd:cd14399   1 RYASQLEQLQAMGFVDRQANIQALIATGGNVNAAIERLLG 40

STI1 domain; This entry corresponds to the STI1 domain that is found in two copies in the Sti1 protein.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....*.
gi 34328236   219 NPQMQQLIQRNPEISHLLNNPDIMRQTLEIARNPAMMQEMMRNQDL 264
Cdd:pfam17830   1 DPELLAKLAANPETRALLSDPEFVAKLQQIQKNPSSLQQYMQDPRV 46

Heat shock chaperonin-binding motif;

                           10        20        30
                   ....*....|....*....|....*....|....*...
gi 34328236    193 MIQIMENPFVQSMLS----NPDLMRQLIMANPQMQQLI 226
Cdd:smart00727   4 MALRLQNPQVQSLLQdmqqNPDMLAQMLQENPQLLQLI 41

UBA domain of eukaryotic protein linking integrin-associated protein (IAP, also known as CD47) with cytoskeleton (PLIC) proteins; The PLIC proteins (or ubiquilins) family contains human homologs of the yeast ubiquitin-like Dsk2 protein, PLIC-1 (also called ubiquilin-1), PLIC-2 (also called ubiquilin-2 or Chap1), PLIC-3 (also called ubiquilin-3) and PLIC-4 (also called ubiquilin-4, Ataxin-1 interacting ubiquitin-like protein, A1Up, Connexin43-interacting protein of 75 kDa, or CIP75), and mouse PLIC proteins. They are ubiquitin-binding adaptor proteins involved in all protein degradation pathways through delivering ubiquitinated substrates to proteasomes. They also promote autophagy-dependent cell survival during nutrient starvation. PLIC-1 regulates the function of the thrombospondin receptor CD47 and G protein signaling. It plays a role in TLR4-mediated signaling through interacting with the Toll/interleukin-1 receptor (TIR) domain of TLR4. It also inhibits the TLR3-Trif antiviral pathway by reducing the abundance of Trif. Moreover, PLIC-1 binds to gamma-aminobutyric acid receptors (GABAARs) and modulates the ubiquitin-dependent, proteasomal degradation of GABAARs. Furthermore, PLIC-1 acts as a molecular chaperone regulating amyloid precursor protein (APP) biosynthesis, trafficking, and degradation by stimulating K63-linked polyubiquitination of lysine 688 in the APP intracellular domain. In addition, PLIC-1 is involved in the protein aggregation-stress pathway via associating with the ubiquitin-interacting motif (UIM) proteins ataxin 3, HSJ1a, and epidermal growth factor substrate 15 (EPS15). PLIC-2 is a protein that binds the ATPase domain of the HSP70-like Stch protein. It functions as a negative regulator of G protein-coupled receptor (GPCR) endocytosis. It also involved in amyotrophic lateral sclerosis (ALS)-related dementia. PLIC-3 is encoded by UBQLN3, a testis-specific gene. It shows high sequence similarity with the Xenopus protein XDRP1, a nuclear phosphoprotein that binds to the N-terminus of cyclin A and inhibits Ca2+-induced degradation of cyclin A, but not cyclin B. PLIC-4 is a ubiquitin-like nuclear protein that interacts with ataxin-1 and further links ataxin-1 with the chaperone and ubiquitin-proteasome pathways. It also binds to the non-ubiquitinated gap junction protein connexin43 (Cx43) and regulates the turnover of Cx43 through the proteasomal pathway. PLIC proteins contain an N-terminal ubiquitin-like (UBL) domain that is responsible for the binding of ubiquitin-interacting motifs (UIMs) expressed by proteasomes and endocytic adaptors, and C-terminal ubiquitin-associated (UBA) domain that interacts with ubiquitin chains present on proteins destined for proteasomal degradation. In addition, mammalian PLIC2 proteins have an extra collagen-like motif region which is absent in other PLIC proteins and the yeast Dsk2 protein.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|
gi 34328236 595 RFQQQLEQLNAMGFLNREANLQALIATGGDINAAIERLLG 634
Cdd:cd14399   1 RYASQLEQLQAMGFVDRQANIQALIATGGNVNAAIERLLG 40

Ubiquitin homologues; Ubiquitin-mediated proteolysis is involved in the regulated turnover of proteins required for controlling cell cycle progression

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 34328236     33 IKVTVKTPKEKE-EFAVPENSTVQQFKEAISKRFKSQTDQLVLIFAGKILKDQDTLMQHGIHDGLTVHLVIK 103
Cdd:smart00213   1 IELTVKTLDGKTiTLEVKPSDTVSELKEKIAELTGIPPEQQRLIYKGKVLEDDRTLADYGIQDGSTIHLVLR 72

Ubiquitin associated domain; Present in Rad23, SNF1-like kinases. The newly-found UBA in p62 is known to bind ubiquitin.

                           10        20        30
                   ....*....|....*....|....*....|....*..
gi 34328236    597 QQQLEQLNAMGFlNREANLQALIATGGDINAAIERLL 633
Cdd:smart00165   2 EEKIDQLLEMGF-SREEALKALRAANGNVERAAEYLL 37

ubiquitin; Provisional

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 34328236   33 IKVTVKT-PKEKEEFAVPENSTVQQFKEAISKRFKSQTDQLVLIFAGKILKDQDTLMQHGIHDGLTVHLVIK 103
Cdd:PTZ00044   1 MQILIKTlTGKKQSFNFEPDNTVQQVKMALQEKEGIDVKQIRLIYSGKQMSDDLKLSDYKVVPGSTIHMVLQ 72

STI1 domain; This entry corresponds to the STI1 domain that is found in two copies in the Sti1 protein.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....*.
gi 34328236   219 NPQMQQLIQRNPEISHLLNNPDIMRQTLEIARNPAMMQEMMRNQDL 264
Cdd:pfam17830   1 DPELLAKLAANPETRALLSDPEFVAKLQQIQKNPSSLQQYMQDPRV 46

Heat shock chaperonin-binding motif;

                           10        20        30
                   ....*....|....*....|....*....|....*...
gi 34328236    193 MIQIMENPFVQSMLS----NPDLMRQLIMANPQMQQLI 226
Cdd:smart00727   4 MALRLQNPQVQSLLQdmqqNPDMLAQMLQENPQLLQLI 41

UBA domain of eukaryotic protein linking integrin-associated protein (IAP, also known as CD47) with cytoskeleton (PLIC) proteins; The PLIC proteins (or ubiquilins) family contains human homologs of the yeast ubiquitin-like Dsk2 protein, PLIC-1 (also called ubiquilin-1), PLIC-2 (also called ubiquilin-2 or Chap1), PLIC-3 (also called ubiquilin-3) and PLIC-4 (also called ubiquilin-4, Ataxin-1 interacting ubiquitin-like protein, A1Up, Connexin43-interacting protein of 75 kDa, or CIP75), and mouse PLIC proteins. They are ubiquitin-binding adaptor proteins involved in all protein degradation pathways through delivering ubiquitinated substrates to proteasomes. They also promote autophagy-dependent cell survival during nutrient starvation. PLIC-1 regulates the function of the thrombospondin receptor CD47 and G protein signaling. It plays a role in TLR4-mediated signaling through interacting with the Toll/interleukin-1 receptor (TIR) domain of TLR4. It also inhibits the TLR3-Trif antiviral pathway by reducing the abundance of Trif. Moreover, PLIC-1 binds to gamma-aminobutyric acid receptors (GABAARs) and modulates the ubiquitin-dependent, proteasomal degradation of GABAARs. Furthermore, PLIC-1 acts as a molecular chaperone regulating amyloid precursor protein (APP) biosynthesis, trafficking, and degradation by stimulating K63-linked polyubiquitination of lysine 688 in the APP intracellular domain. In addition, PLIC-1 is involved in the protein aggregation-stress pathway via associating with the ubiquitin-interacting motif (UIM) proteins ataxin 3, HSJ1a, and epidermal growth factor substrate 15 (EPS15). PLIC-2 is a protein that binds the ATPase domain of the HSP70-like Stch protein. It functions as a negative regulator of G protein-coupled receptor (GPCR) endocytosis. It also involved in amyotrophic lateral sclerosis (ALS)-related dementia. PLIC-3 is encoded by UBQLN3, a testis-specific gene. It shows high sequence similarity with the Xenopus protein XDRP1, a nuclear phosphoprotein that binds to the N-terminus of cyclin A and inhibits Ca2+-induced degradation of cyclin A, but not cyclin B. PLIC-4 is a ubiquitin-like nuclear protein that interacts with ataxin-1 and further links ataxin-1 with the chaperone and ubiquitin-proteasome pathways. It also binds to the non-ubiquitinated gap junction protein connexin43 (Cx43) and regulates the turnover of Cx43 through the proteasomal pathway. PLIC proteins contain an N-terminal ubiquitin-like (UBL) domain that is responsible for the binding of ubiquitin-interacting motifs (UIMs) expressed by proteasomes and endocytic adaptors, and C-terminal ubiquitin-associated (UBA) domain that interacts with ubiquitin chains present on proteins destined for proteasomal degradation. In addition, mammalian PLIC2 proteins have an extra collagen-like motif region which is absent in other PLIC proteins and the yeast Dsk2 protein.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|
gi 34328236 595 RFQQQLEQLNAMGFLNREANLQALIATGGDINAAIERLLG 634
Cdd:cd14399   1 RYASQLEQLQAMGFVDRQANIQALIATGGNVNAAIERLLG 40

ubiquitin-like (Ubl) domain found in Saccharomyces cerevisiae proteasome interacting protein Dsk2p and similar proteins; The family contains several fungal multiubiquitin receptors, including Saccharomyces cerevisiae Dsk2p and Schizosaccharomyces pombe Dph1p, both of which have been characterized as shuttle proteins transporting ubiquitinated substrates destined for degradation from the E3 ligase to the 26S proteasome. They interact with the proteasome through their N-terminal ubiquitin-like domain (Ubl) and with ubiquitin (Ub) through their C-terminal Ub-associated domain (UBA). S. cerevisiae Dsk2p is a nuclear-enriched protein that may involve in the ubiquitin-proteasome proteolytic pathway through interacting with K48-linked polyubiquitin and the proteasome. Moreover, it has been implicated in spindle pole duplication through assisting in Cdc31 assembly into the new spindle pole body (SPB). S. pombe Dph1p is an ubiquitin (Ub0 receptor working in concert with the class V myosin, Myo52, to target the degradation of the S. pombe CLIP-170 homolog, Tip1. It also can protect Ub chains against disassembly by deubiquitinating enzymes.

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 34328236  33 IKVTVKTPKEKE-EFAVPENSTVQQFKEAISKRFKSQTDQLVLIFAGKILKDQDTLMQHGIHDGLTVHLV 101
Cdd:cd16106   1 IKVTVKCSNGKKfTVEVEPDATVLELKELIAEKSDIPAEQQRLIYKGKILKDEETLSSYKIQDGHTVHLV 70

Ubiquitin homologues; Ubiquitin-mediated proteolysis is involved in the regulated turnover of proteins required for controlling cell cycle progression

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 34328236     33 IKVTVKTPKEKE-EFAVPENSTVQQFKEAISKRFKSQTDQLVLIFAGKILKDQDTLMQHGIHDGLTVHLVIK 103
Cdd:smart00213   1 IELTVKTLDGKTiTLEVKPSDTVSELKEKIAELTGIPPEQQRLIYKGKVLEDDRTLADYGIQDGSTIHLVLR 72

ubiquitin-like (Ubl) domain found in BCL2-associated athanogene 6 (BAG6) and similar proteins; BAG6, also termed large proline-rich protein BAG6, or BAG family molecular chaperone regulator 6, or HLA-B-associated transcript 3 (Bat3), or protein Scythe, or protein G3, is a nucleo-cytoplasmic shuttling chaperone protein that is highly conserved in eukaryotes. It functions in two distinct biological pathways, ubiquitin-mediated protein degradation of defective polypeptides and tail-anchored transmembrane protein biogenesis in mammals. BAG6 is a component of the heterotrimeric BAG6 sortase complex composed of BAG6, transmembrane recognition complex 35 (TRC35) and ubiquitin-like protein 4A (UBL4A). The BAG6 complex together with the cochaperone small, glutamine-rich, tetratricopeptide repeat-containing, protein alpha (SGTA) plays a role in the biogenesis of tail-anchored membrane proteins and subsequently shown to regulate the ubiquitination and proteasomal degradation of mislocalized proteins. Moreover, BAG6 acts as an apoptotic regulator that binds reaper, a potent apoptotic inducer. BAG6/reaper is thought to signal apoptosis, in part through regulating the folding and activity of apoptotic signaling molecules. It is also likely a key regulator of the molecular chaperone Heat Shock Protein A2 (HSPA2) stability/function in human germ cells. Furthermore, aspartyl protease-mediated cleavage of BAG6 is necessary for autophagy and fungal resistance in plants. BAG6 contains a ubiquitin-like (Ubl) domain with a beta-grasp Ubl fold, which provides a platform for discriminating substrates with shorter hydrophobicity stretches as a signal for defective proteins.

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 34328236  33 IKVTVKT-PKEKEEFAVPENSTVQQFKEAISKRFKSQTDQLVLIFAGKILKDQDTLMQHGIHdGLTVHLV 101
Cdd:cd01809   1 LEVTVKTlDSQNRTFTVPEEITVKEFKEHIASSVNIPAEKQRLIFQGRVLQDDKKLKEYDVD-GKVIHLV 69

UBA domain found in Saccharomyces cerevisiae protein GTS1 (Gts1p) and similar proteins; Gts1p, also called protein LSR1, is encoded by a pleiotropic gene GTS1 in budding yeast. The formation of Gts1p-mediated protein aggregates may induce reactive oxygen species (ROS) production and apoptosis. Gts1p also plays an important role in the regulation of heat and other stress responses under glucose-limited or -depleted conditions in either batch or continuous culture. Gts1p contains an N-terminal zinc finger motif similar to that of GATA-transcription factors, a ubiquitin-associated (UBA) domain and a C-terminal glutamine-rich strand. The zinc finger is responsible for the binding to the glycolytic enzyme glyceraldehydes-3-phosphate dehydrogenase (GAPDH) which is required for the maintenance of the metabolic oscillations of budding yeast. The polyglutamine sequence is indispensable for the pleiotropy and nuclear localization of Gts1p. It is essential for the transcriptional activation, whereas Gts1p lacks DNA binding activity.

                        10        20        30
                ....*....|....*....|....*....|....*....
gi 34328236 595 RFQQQLEQLNAMGFLNREANLQALIATGGDINAAIERLL 633
Cdd:cd14400   1 KYSRQLRFLKEMGFTNEDNNLEALSQANGNINRAIDILL 39

Beta-grasp ubiquitin-like fold; Ubiquitin is a protein modifier that is involved in various cellular processes including transcriptional regulation, cell cycle control, and DNA repair in eukaryotes. The ubiquitination process comprises a cascade of E1, E2 and E3 enzymes that results in a covalent bond between the C-terminus of ubiquitin and the epsilon-amino group of a substrate lysine. Ubiquitin-like proteins have similar ubiquitin beta-grasp fold and attach to other proteins in a ubiquitin-like manner but with biochemically distinct roles. Ubiquitin and ubiquitin-like proteins conjugate and deconjugate via ligases and peptidases to covalently modify target polypeptides. Some other ubiquitin-like domains have adaptor roles in ubiquitin-signaling by mediating protein-protein interaction. In addition to Ubiquitin-like (Ubl) domain, Ras-associating (RA) domain, F0/F1 sub-domain of FERM (Four.1 protein, Ezrin, Radixin, Moesin) domain, TGS (ThrRS, GTPase and SpoT) domain, Ras-binding domain (RBD), Ubiquitin regulatory domain X (UBX), Dublecortin-like domain, and RING finger- and WD40-associated ubiquitin-like (RAWUL) domain have beta-grasp ubiquitin-like folds, and are included in this superfamily.

                        10        20        30        40        50        60
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....
gi 34328236  33 IKVTVKTPKEKEeFAVPENSTVQQFKEAISKRFKSQTDQLVLIFAGKILKDQDTLMQHGIHDGLTVHLV 101
Cdd:cd00196   1 VKVETPSLKKIV-VAVPPSTTLRQVLEKVAKRIGLPPDVIRLLFNGQVLDDLMTAKQVGLEPGEELHFV 68

UBA domain found in ubiquitin-like protein 7 (UBL7) and similar proteins; UBL7, also called bone marrow stromal cell ubiquitin-like protein (BMSC-UbP), or ubiquitin-like protein SB132, is a novel ubiquitin-like protein that may play roles in regulation of bone marrow stromal cell (BMSC) function or cell differentiation via an evocator-associated and cell-specific pattern. UBL7 contains an N-terminal ubiquitin domain (UBQ) and a C-terminal ubiquitin-associated (UBA) domain. UBQ domain interacts with 26S proteasome-dependent degradation, and UBA domain links cellular processes and the ubiquitin system.

                        10        20        30
                ....*....|....*....|....*....|....*...
gi 34328236 596 FQQQLEQLNAMGFLNREANLQALIATGGDINAAIERLL 633
Cdd:cd14326   1 LQSQLQQLREMGITDDSLSLRALQATGGDVQAALNLLF 38

ubiquitin-like (Ubl) domain found in homocysteine-inducible endoplasmic reticulum stress protein HERP; HERP is an endoplasmic reticulum (ER) integral membrane protein containing an N-terminal ubiquitin-like (Ubl) domain with a beta-grasp Ubl fold. The Ubl domain is required for the degradation of HERP itself as well as for HERP-mediated anti-apoptotic effects. HERP is induced by the ER stress response pathway and is involved in improving the balance of folding capacity and protein loads in the ER. There are two types of HERP, HERP1 and HERP2, which are encoded by the HERPUD1 and HERPUD2 genes, respectively.

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 34328236  33 IKVTVKTPKEK---EEFAVPENSTVQQFKEAISKRF--KSQTDQLVLIFAGKILKD----QDTLMQHGIHDGLTVHLV 101
Cdd:cd01790   1 VTLVVKSPNQRiqdLTVNCTLGWTVLKLKEHLSEVYpsKPLPEDQKLIYSGKLLEDhqtlKDVLREDDPEQVHTVHLV 78

Ubiquitin associated domain; Present in Rad23, SNF1-like kinases. The newly-found UBA in p62 is known to bind ubiquitin.

                           10        20        30
                   ....*....|....*....|....*....|....*..
gi 34328236    597 QQQLEQLNAMGFlNREANLQALIATGGDINAAIERLL 633
Cdd:smart00165   2 EEKIDQLLEMGF-SREEALKALRAANGNVERAAEYLL 37

ubiquitin-like (Ubl) domain 2 found in interferon-stimulated gene 15 (ISG15) and similar proteins; ISG15, also termed interferon-induced 15 kDa protein, or interferon-induced 17 kDa protein (IP17), or ubiquitin cross-reactive protein (UCRP), is an antiviral interferon-induced ubiquitin-like protein that upon viral infection it modifies cellular and viral proteins by mechanisms similar to ubiquitination. Although ISG15 has properties similar to those of other ubiquitin-like (Ubl) molecules, it is a unique member of the Ubl superfamily, whose expression and conjugation to target proteins are tightly regulated by specific signaling pathways, indicating it may have specialized functions in the immune system. ISG15 contains two tandem Ubl domains with a beta-grasp Ubl fold. This family corresponds to the second Ubl domain.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....*
gi 34328236  46 FAVPENSTVQQFKEAISKRFKSQTDQLVLIFAGKILKDQDTLMQHGIHDGLTVHL 100
Cdd:cd01810  15 YEVRLTQTVDQLKQKVSGREGVHDDQFWLTFEGRPLEDQLPLGEYGLKPQSTIHM 69

ubiquitin-like (Ubl) domain found in parkin and similar proteins; Parkin, also termed Parkinson juvenile disease protein 2, is a RBR-type E3 ubiquitin-protein ligase that is associated with recessive early onset Parkinson's disease (PD), and exerts a protective effect against dopamine-induced alpha-synuclein-dependent cell toxicity. Mutations in the parkin gene cause autosomal recessive juvenile parkinsonism. Parkin functions within a multiprotein E3 ubiquitin ligase complex, catalyzing the covalent attachment of ubiquitin moieties onto substrate proteins, such as BCL2, SYT11, CCNE1, GPR37, RHOT1/MIRO1, MFN1, MFN2, STUB1, SNCAIP, SEPT5, TOMM20, USP30, ZNF746 and AIMP2. It mediates monoubiquitination as well as Lys-6-, Lys-11-, Lys-48- and Lys-63-linked polyubiquitination of substrates depending on the context. Parkin may enhance cell viability and protects dopaminergic neurons from oxidative stress-mediated death by regulating mitochondrial function. It also limits the production of reactive oxygen species (ROS), and regulates cyclin-E during neuronal apoptosis. Moreover, parkin displays a ubiquitin ligase-independent function in transcriptional repression of p53. Parkin contains an N-terminal ubiquitin-like (Ubl) domain and a C-terminal RBR domain that was previously known as RING-BetweenRING-RING domain or TRIAD [two RING fingers and a DRIL (double RING finger linked)] domain. Based on current understanding of the structural biology of RBR ligases, the nomenclature of RBR has been corrected as RING-BRcat (benign-catalytic)-Rcat (required-for-catalysis) recently. The RBR (RING1-BRcat-Rcat) domain use an auto-inhibitory mechanism to modulate ubiquitination activity, as well as a hybrid mechanism that combines aspects from both RING and HECT E3 ligase function to facilitate the ubiquitination reaction.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....*...
gi 34328236  53 TVQQFKEAISKRFKSQTDQLVLIFAGKILKDQDTLMQHGIHDGLTVHLViksQNRPQG 110
Cdd:cd01798  20 SILQLKEVVAKRQGVPPDQLRIIFAGKELSDDLTLQNCDLGQQSIVHAV---QGPKRK 74

ubiquitin; Provisional

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 34328236   33 IKVTVKT-PKEKEEFAVPENSTVQQFKEAISKRFKSQTDQLVLIFAGKILKDQDTLMQHGIHDGLTVHLVIK 103
Cdd:PTZ00044   1 MQILIKTlTGKKQSFNFEPDNTVQQVKMALQEKEGIDVKQIRLIYSGKQMSDDLKLSDYKVVPGSTIHMVLQ 72

ubiquitin-like (Ubl) domain 1 found in Ankyrin repeat and ubiquitin domain-containing 1 (ANKUB1) and similar proteins; ANKUB1 is an uncharacterized protein with two tandem ubiquitin-like (Ubl) domains located at the N-terminal of Ankyrin repeats (ANK). The Ubl domain may have an adaptor role in ubiquitin (Ub)-signaling by mediating protein-protein interaction. Ubl proteins have a beta-grasp Ubl fold and attach to other proteins in a Ubl manner with biochemically distinct roles. The ankyrin repeats have been identified in numerous proteins with diverse functions. The family corresponds to the first Ubl domain.

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 34328236  41 KEKEEFAVPENSTVQQFKEAISKRFKSQTDQ-------LVLIFAGKILKDQDTLMQHGIHDGLTVHLVIK 103
Cdd:cd17050   9 GEREPLDVSPGQTVGDVKEMIRDKFHIDLSDgkqgrkfLVLTYAGADLQDSWVLSDIGIPPGSTIRCLLR 78

ubiquitin-like (Ubl) domain found in neural precursor cell expressed developmentally down-regulated protein 8 (NEDD8) and similar proteins; NEDD8, also termed Neddylin, or RELATED TO UBIQUITIN (RUB/Rub1p) in plant and yeast, is a ubiquitin-like protein that conjugates to nuclear proteins in a manner analogous to ubiquitination and sentrinization. It modifies a family of molecular scaffold proteins called cullins that are responsible for assembling the ROC1/Rbx1 RING-based E3 ubiquitin ligases, of which several play a direct role in tumorigenesis. NEDD8 deamidation and its inhibition of Cullin-RING ubiquitin ligases (CRLs) activity are responsible for Cycle-inhibiting factor (Cif)/Cif homolog in Burkholderia pseudomallei (CHBP)-induced cytopathic effect. NEDD8 contains a single conserved ubiquitin-like (Ubl) domain with a beta-grasp Ubl fold, a common structure involved in protein-protein interactions. Polyubiquitination, signals for a diverse set of cellular events via different isopeptide linkages formed between the C terminus of one ubiquitin (Ub) and the epsilon-amine of K6, K11, K27, K29, K33, K48, or K63 of a second Ub. Ubl NEDD8, contains many of the same lysines (K6, K11, K27, K33, K48) as Ub, where K27 has an role (other than conjugation) in the mechanism of protein neddylation.

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 34328236  33 IKVTVKTPKEKEeFAVPENSTVQQFKEAISKRFKSQTDQLVLIFAGKILKDQDTLMQHGIHDGLTVHLVI 102
Cdd:cd01806   1 IKVKTLTGKEIE-IDIEPTDKVERIKERVEEKEGIPPQQQRLIFSGKQMNDEKTAADYKIEGGSVLHLVL 69

UBA domain of next to BRCA1 gene 1 protein (NBR1) and similar proteins; NBR1, also called cell migration-inducing gene 19 protein, membrane component chromosome 17 surface marker 2, neighbor of BRCA1 gene 1 protein, or protein 1A1-3B, is a scaffold protein that may be involved in signal transmission downstream of the serine/protein kinase from the giant muscle protein titin. Moreover, NBR1 functions as an autophagic receptor for ubiquitinated cargo. It interacts with ATG8-family proteins for its degradation by autophagy. NBR1 contains an N-terminal Phox and Bem1p (PB1) domain that plays a critical role in mediating protein-protein interactions with both titin kinase and with another scaffold protein, p62. NBR1 also has a LC3-interaction region (LIR) and a ubiquitin-associated (UBA) domain. The LIR is required for the autophagic clearance of NBR1. UBA domain is responsible for the ubiquitin binding which is necessary for the puromycin-induced formation of ubiquitinated protein aggregates.

                        10        20        30
                ....*....|....*....|....*....|....*
gi 34328236 599 QLEQLNAMGFLNREANLQALIATGGDINAAIERLL 633
Cdd:cd14319   5 ELEQLFEMGFTDRDLNQELLKKHNGDLDRVVDELL 39

ubiquitin-like (Ubl) domain found in transmembrane and ubiquitin-like domain-containing proteins TMUB1, TMUB2, and similar proteins; TMUB1, also termed dendritic cell-derived ubiquitin-like protein (DULP), or hepatocyte odd protein shuttling protein, or ubiquitin-like protein SB144, or HOPS, is highly expressed in the nervous system. It is involved in the termination of liver regeneration and plays a negative role in interleukin-6-induced hepatocyte proliferation. The overexpression of Tmub1 has been shown to play a role in the inhibition of cell proliferation. TMUB1 has been implicated in the regulation of locomotor activity and wakefulness in mice, perhaps acting through its interaction with CAMLG. It also facilitates the recycling of AMPA receptors into synaptic membrane in cultured primary neurons. TMUB1 contains transmembrane domains and a ubiquitin-like (Ubl) domain with a beta-grasp Ubl fold. TMUB2 is an uncharacterized transmembrane domain and Ubl domain-containing protein that shows high sequence similarity to TMUB1.

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                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 34328236  32 IIKVTVKTPKEKEEFA-VPENSTVQQFKeaiSKRFKSQTDQ--LV-LIFAGKILKDQ-DTLMQHGIHDGLTVHLVI 102
Cdd:cd17057   1 TITIRLKFLNETERVVyARPEDTVGDFK---RRHFPDELAQgkRVrLIYQGQLLRDDsRTLSSYGIQDGSVIHCHI 73

ubiquitin-like (Ubl) domain found in ubiquitin; Ubiquitin is a protein modifier in eukaryotes that is involved in various cellular processes, including transcriptional regulation, cell cycle control, and DNA repair. Ubiquitination is comprised of a cascade of E1, E2 and E3 enzymes that results in a covalent bond between the C-terminus of ubiquitin and the epsilon-amino group of a substrate lysine. Ubiquitin-like (Ubl) proteins have similar ubiquitin beta-grasp fold and attach to other proteins in a Ubl manner but with biochemically distinct roles. Ubiquitin (Ub)and Ubl proteins conjugate and deconjugate via ligases and peptidases to covalently modify target polypeptides. Ub includes Ubq/RPL40e and Ubq/RPS27a fusions as well as homopolymeric multiubiquitin protein chains.

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 34328236  33 IKVTVKTPKEKE-EFAVPENSTVQQFKEAISKRFKSQTDQLVLIFAGKILKDQDTLMQHGIHDGLTVHLVIK 103
Cdd:cd01803   1 MQIFVKTLTGKTiTLEVEPSDTIENVKAKIQDKEGIPPDQQRLIFAGKQLEDGRTLSDYNIQKESTLHLVLR 72

ubiquitin-like (Ubl) domain found in autophagy-related 8 (ATG8) and similar proteins; The ATG8 family of proteins constitute a single member in Saccharomyces cerevisiae, Atg8p, and multiple homologs in higher eukaryotes, they are multifunctional ubiquitin-like (Ubl) key regulators of autophagy. The ATG8 system is a Ubl conjugation system that is essential for autophagosome formation. In the ATG8 system, a cysteine protease (ATG4) cleaves a C-terminal arginine from ATG8, and then the exposed C-terminal glycine is conjugated to phosphatidylethanolamine (PE) by ATG7, an E1-like enzyme, and ATG3, an E2-like enzyme. The mammalian ATG8 family is classified into three subfamilies: i) MAP1LC3 (microtubule associated protein 1 light chain 3) which includes MAP1LC3A, MAP1LC3B, MAP1LC3B2, and MAP1LC3C, ii) GABARAP (GABA type A receptor associated protein) which includes GABARAP, GABARAPL1, and GABARAPL3, and iii) GABARAPL2 (GABA type A receptor associated protein like 2), also known as GATE-16 (golgi-associated adenosine triphosphatase enhancer of 16 kDa).

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*....
gi 34328236  42 EKEEFAVPENSTVQQFKEAISKRFKSQTDQLVLIFAGKILKDQDTLMQH 90
Cdd:cd16108  19 DKKKFLVPSDLTVGQFMYIIRKRIKLSPEKAIFLFVNNTLPPTSALMSE 67

UBA domain found in ubiquitin-associated domain-containing protein 2 (UBAC2) and similar proteins; UBAC2, also called phosphoglycerate dehydrogenase-like protein 1, is a ubiquitin-associated domain (UBA)-domain containing protein encoded by gene UBAC2 (or PHGDHL1), a risk gene for Behcet's disease (BD). It may play an important role in the development of BD through its transcriptional modulation. Members in this family contain an N-terminal rhomboid-like domain and a C-terminal UBA domain.

                        10        20        30
                ....*....|....*....|....*....|....*
gi 34328236 599 QLEQLNAMGFlNREANLQALIATGGDINAAIERLL 633
Cdd:cd14305   5 QVQQLVDMGF-SREDVLEALRQSNNDVNAATNLLL 38

ubiquitin-like (Ubl) domain found in ubiquitin carboxyl-terminal hydrolase 24 (UBP24) and similar proteins; UBP24 (EC 3.4.19.12), also termed deubiquitinating enzyme 24, or ubiquitin thioesterase 24, or ubiquitin-specific-processing protease 24 (USP24), is a deubiquitinating protein that interacts with damage-specific DNA-binding protein 2 (DDB2) and regulates DDB2 stability. It may also play a role in the pathogenesis of Parkinson's disease (PD). UBP24 proteins contain an N-terminal ubiquitin-associated (UBA) domain, a ubiquitin-like (Ubl) domain, and a C-terminal peptidase C19 domain.

                        10        20        30        40        50        60        70
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|.
gi 34328236  33 IKVTVKTPKEKEEFAVP--ENSTVQQFKEAISKRFKSQTDQLVLIFAGKIL---KDQDTLMQHGIHDGLTV 98
Cdd:cd17065   6 LTLHVTCESTKQEFTLEvhSNETLGSVRQKIAERLNCPVDQVQIFANEKLLpsnKDQKLLHQLGFTDEQIL 76

Domain of unknown function (DUF4175);

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 34328236   395 QLIQNMLSA--PYMRSMMQSLSQNPDMAAQMMlssplftsNPQLQeQMRPQ-LPNFLQQMQNpetiAAMSNPR--AMQAL 469
Cdd:pfam13779 513 KLMQELREAldDYMQALAEQAQQNPQDLQQPD--------DPNAQ-EMTQQdLQRMLDRIEE----LARSGRRaeAQQML 579

                          90
                  ....*....|....*.
gi 34328236   470 MQIQQGLQTLATEAPG 485
Cdd:pfam13779 580 SQLQQMLENLQAGQPQ 595