ubiquitin-like (Ubl) domain found in ubiquitin-like protein 5 (UBL5) and similar proteins; UBL5, known as Hub1 in yeast, is an atypical ubiquitin-like (Ubl) post-translational modifier that contains a conserved Ubl domain with a beta-grasp Ubl fold. At the C-terminal end of its Ubl fold is a di-tyrosine motif followed by a single variable residue instead of the characteristic di-glycine found in all other Ubl modifiers, and thus UBL5 does not form covalent conjugates with cellular proteins. The yeast Hub1p binds non-covalently to the HIND element of spliceosomal protein Snu66p (Snu66p is termed SART1 in mammals) and modifies the spliceosome by this unconventional Ubl modifier. In higher eukaryotes, UBL5/Hub1 plays a role in modulating pre-mRNA splicing. It also is required for signaling in the mitochondrial unfolded protein response, through interaction with the transcription factor DVE-1 and upregulation of chaperone genes in response to mitochondrial stress. Moreover, UBL5 functions as a factor that directly binds to and stabilizes FANCI, and promotes the functionality of the Fanconi anemia (FA) DNA repair pathway.

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               ....*....|....*....|....*....|....*....|....*....|....*....|....*....|.
gi 6324360   1 MIEVVVNDRLGKKVRVKCLAEDSVGDFKKVLSLQIGTQPNKIVLQKGGSVLKDHISLEDYEVHDQTNLELY 71
Cdd:cd01791  1 MIEVICNDRLGKKVRVKCNPDDTIGDLKKLIAAQTGTRPEKIVLKKWYTIFKDHITLEDYEIHDGMNLELY 71

ubiquitin-like (Ubl) domain found in ubiquitin-like protein 5 (UBL5) and similar proteins; UBL5, known as Hub1 in yeast, is an atypical ubiquitin-like (Ubl) post-translational modifier that contains a conserved Ubl domain with a beta-grasp Ubl fold. At the C-terminal end of its Ubl fold is a di-tyrosine motif followed by a single variable residue instead of the characteristic di-glycine found in all other Ubl modifiers, and thus UBL5 does not form covalent conjugates with cellular proteins. The yeast Hub1p binds non-covalently to the HIND element of spliceosomal protein Snu66p (Snu66p is termed SART1 in mammals) and modifies the spliceosome by this unconventional Ubl modifier. In higher eukaryotes, UBL5/Hub1 plays a role in modulating pre-mRNA splicing. It also is required for signaling in the mitochondrial unfolded protein response, through interaction with the transcription factor DVE-1 and upregulation of chaperone genes in response to mitochondrial stress. Moreover, UBL5 functions as a factor that directly binds to and stabilizes FANCI, and promotes the functionality of the Fanconi anemia (FA) DNA repair pathway.

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               ....*....|....*....|....*....|....*....|....*....|....*....|....*....|.
gi 6324360   1 MIEVVVNDRLGKKVRVKCLAEDSVGDFKKVLSLQIGTQPNKIVLQKGGSVLKDHISLEDYEVHDQTNLELY 71
Cdd:cd01791  1 MIEVICNDRLGKKVRVKCNPDDTIGDLKKLIAAQTGTRPEKIVLKKWYTIFKDHITLEDYEIHDGMNLELY 71

Ubiquitin family; This family contains a number of ubiquitin-like proteins: SUMO (smt3 homolog), Nedd8, Elongin B, Rub1, and Parkin. A number of them are thought to carry a distinctive five-residue motif termed the proteasome-interacting motif (PIM), which may have a biologically significant role in protein delivery to proteasomes and recruitment of proteasomes to transcription sites.

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gi 6324360    11 GKKVRVKCLAEDSVGDFKKVLSLQIGTQPNKIVLQKGGSVLKDHISLEDYEVHDQTNLELY 71
Cdd:pfam00240  8 GKKITLEVDPTDTVLELKEKIAEKEGVPPEQQRLIYSGKVLEDDQTLGEYGIEDGSTIHLV 68

ubiquitin-like (Ubl) domain found in ubiquitin-like protein 5 (UBL5) and similar proteins; UBL5, known as Hub1 in yeast, is an atypical ubiquitin-like (Ubl) post-translational modifier that contains a conserved Ubl domain with a beta-grasp Ubl fold. At the C-terminal end of its Ubl fold is a di-tyrosine motif followed by a single variable residue instead of the characteristic di-glycine found in all other Ubl modifiers, and thus UBL5 does not form covalent conjugates with cellular proteins. The yeast Hub1p binds non-covalently to the HIND element of spliceosomal protein Snu66p (Snu66p is termed SART1 in mammals) and modifies the spliceosome by this unconventional Ubl modifier. In higher eukaryotes, UBL5/Hub1 plays a role in modulating pre-mRNA splicing. It also is required for signaling in the mitochondrial unfolded protein response, through interaction with the transcription factor DVE-1 and upregulation of chaperone genes in response to mitochondrial stress. Moreover, UBL5 functions as a factor that directly binds to and stabilizes FANCI, and promotes the functionality of the Fanconi anemia (FA) DNA repair pathway.

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               ....*....|....*....|....*....|....*....|....*....|....*....|....*....|.
gi 6324360   1 MIEVVVNDRLGKKVRVKCLAEDSVGDFKKVLSLQIGTQPNKIVLQKGGSVLKDHISLEDYEVHDQTNLELY 71
Cdd:cd01791  1 MIEVICNDRLGKKVRVKCNPDDTIGDLKKLIAAQTGTRPEKIVLKKWYTIFKDHITLEDYEIHDGMNLELY 71

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

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gi 6324360     11 GKKVRVKCLAEDSVGDFKKVLSLQIGTQPNKIVLQKGGSVLKDHISLEDYEVHDQTNLELY 71
Cdd:smart00213 10 GKTITLEVKPSDTVSELKEKIAELTGIPPEQQRLIYKGKVLEDDRTLADYGIQDGSTIHLV 70

ubiquitin-like (Ubl) domain found in 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 (Ubl) Dsk2 protein, PLIC-1 (also termed ubiquilin-1), PLIC-2 (also termed ubiquilin-2, or Chap1), PLIC-3 (also termed ubiquilin-3) and PLIC-4 (also termed ubiquilin-4, ataxin-1 interacting ubiquitin-like protein, A1Up, connexin43-interacting protein of 75 kDa, or CIP75), and mouse PLIC proteins. They are ubiquitin (Ub)-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 Ub-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 Ub-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 UbiquilinN3, 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 an ubiquitin-like (Ubl) nuclear protein that interacts with ataxin-1 and further links ataxin-1 with the chaperone and Ub-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 Ubl domain that is responsible for the binding of Ub-interacting motifs (UIMs) expressed by proteasomes and endocytic adaptors, and C-terminal Ub-associated (UBA) domain that interacts with Ub 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.

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gi 6324360  23 SVGDFKKVLSLQIGTQPNKIVLQKGGSVLKDHISLEDYEVHD 64
Cdd:cd01808 23 SVKEFKEEISKKFKAPVEQLVLIFAGKILKDQDTLSQHGIKD 64

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.

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gi 6324360  11 GKKVRVKCLAEDSVGDFKKVLSLQIGTQPNKIVLQKGGSVLKDHISLEDYEVHD 64
Cdd:cd16106 10 GKKFTVEVEPDATVLELKELIAEKSDIPAEQQRLIYKGKILKDEETLSSYKIQD 63