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

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gi 226695888   165 MTVRLKFLNETEEVAMVRPNDTIGMLKSKYFPGQ----EQQmKLIFQGQLLHDsSQTLCSLHITDNCVIHCH 232
Cdd:smart00213   1 IELTVKTLDGKTITLEVKPSDTVSELKEKIAELTgippEQQ-RLIYKGKVLED-DRTLADYGIQDGSTIHLV 70

ubiquitin-like (Ubl) domain found in transmembrane and ubiquitin-like domain-containing protein 1 (TMUB1); 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 also 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.

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gi 226695888 165 MTVRLKFLNETEEVAMVRPNDTIGMLKSKYFPGQEQQMKLIFQGQLLHDSSQTLCSLHITDNCVIHCHRS 234
Cdd:cd17131    2 IVLRLKFLNDTERLARVKPEDTIGSLKRTYFPGQEHQVRLIYQGQLLGDDSQTLASLHLTDNCVLHCHIS 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 226695888   165 MTVRLKFLNETEEVAMVRPNDTIGMLKSKYFPGQ----EQQmKLIFQGQLLHDsSQTLCSLHITDNCVIHCH 232
Cdd:smart00213   1 IELTVKTLDGKTITLEVKPSDTVSELKEKIAELTgippEQQ-RLIYKGKVLED-DRTLADYGIQDGSTIHLV 70

ubiquitin-like (Ubl) domain found in ubiquitin and ubiquitin-like Ubl proteins; Ubiquitin-like (Ubl) proteins have a similar ubiquitin (Ub) beta-grasp fold and attach to other proteins in a Ubl manner but with biochemically distinct roles. Ub and Ubl proteins conjugate and deconjugate via ligases and peptidases to covalently modify target polypeptides. Some Ubl domains have adaptor roles in Ub-signaling by mediating protein-protein interaction. Prokaryotic sulfur carrier proteins are Ub-related proteins that can be activated in an ATP-dependent manner. 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. One of these seven lysine residues (K27, Ub numbering) is conserved in this Ubl_ubiquitin_like family. K27-linked Ub chains are versatile and can be recognized by several downstream receptor proteins. K27 has roles beyond chain linkage, such as in Ubl NEDD8 (which contains many of the same lysines (K6, K11, K27, K33, K48) as Ub) where K27 has a role (other than conjugation) in the mechanism of protein neddylation.

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gi 226695888 167 VRLKFLNETEEVAMVRPNDTIGMLKSK---YFPGQEQQMKLIFQGQLLHDsSQTLCSLHITDNCVIHCH 232
Cdd:cd17039    1 ITVKTLDGKTYTVEVDPDDTVADLKEKieeKTGIPVEQQRLIYNGKELKD-DKTLSDYGIKDGSTIHLV 68

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 226695888 163 ALMTVRLKFLNETEEVaMVRPNDTIGMLK---SKYFPGQEQQMKLIFQGQLLHDsSQTLCSLHITDNCVIH 230
Cdd:cd01808    1 SIIKVTVKTPKEKEDF-EVPEDSSVKEFKeeiSKKFKAPVEQLVLIFAGKILKD-QDTLSQHGIKDGLTVH 69