The PB1 domain is an essential part of p62 scaffold protein (alias sequestosome 1,SQSTM) involved in cell signaling, receptor internalization, and protein turnover. The PB1 domain is a modular domain mediating specific protein-protein interaction which play roles in many critical cell processes. A canonical PB1-PB1 interaction, which involves heterodimerization of two PB1 domains, is required for the formation of macromolecular signaling complexes ensuring specificity and fidelity during cellular signaling. The interaction between two PB1 domain depends on the type of PB1. There are three types of PB1 domains: type I which contains an OPCA motif, acidic aminoacid cluster, type II which contains a basic cluster, and type I/II which contains both an OPCA motif and a basic cluster. Interactions of PB1 domains with other protein domains have been described as noncanonical PB1-interactions. The PB1 domain module is conserved in amoebas, fungi, animals, and plants.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 31581536   4 LTVKAYLLGKEeAAREIRRFSFCfspepeaeaAAGPGPCERLLSRVAVLFPALRPGGFQAHYRDEDGDLVAFSSDEELTM 83
Cdd:cd06402   1 LTVKAYLLGKD-ANAEIRRFAID---------EDVSTSYEYLVEKVAAVFPSLRGKNFQLFWKDEEGDLVAFSSDEELVM 70

                        90
                ....*....|....*..
gi 31581536  84 AMSYVKDDIFRIYIKEK 100
Cdd:cd06402  71 ALGSLNDDTFRIYIKEK 87

The PB1 domain is an essential part of p62 scaffold protein (alias sequestosome 1,SQSTM) involved in cell signaling, receptor internalization, and protein turnover. The PB1 domain is a modular domain mediating specific protein-protein interaction which play roles in many critical cell processes. A canonical PB1-PB1 interaction, which involves heterodimerization of two PB1 domains, is required for the formation of macromolecular signaling complexes ensuring specificity and fidelity during cellular signaling. The interaction between two PB1 domain depends on the type of PB1. There are three types of PB1 domains: type I which contains an OPCA motif, acidic aminoacid cluster, type II which contains a basic cluster, and type I/II which contains both an OPCA motif and a basic cluster. Interactions of PB1 domains with other protein domains have been described as noncanonical PB1-interactions. The PB1 domain module is conserved in amoebas, fungi, animals, and plants.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 31581536   4 LTVKAYLLGKEeAAREIRRFSFCfspepeaeaAAGPGPCERLLSRVAVLFPALRPGGFQAHYRDEDGDLVAFSSDEELTM 83
Cdd:cd06402   1 LTVKAYLLGKD-ANAEIRRFAID---------EDVSTSYEYLVEKVAAVFPSLRGKNFQLFWKDEEGDLVAFSSDEELVM 70

                        90
                ....*....|....*..
gi 31581536  84 AMSYVKDDIFRIYIKEK 100
Cdd:cd06402  71 ALGSLNDDTFRIYIKEK 87

UBA domain of sequestosome-1 (SQSTM) and similar proteins; SQSTM, also called EBI3-associated protein of 60 kDa (EBIAP /p60), phosphotyrosine-independent ligand for the Lck SH2 domain of 62 kDa, or ubiquitin-binding protein p62, is a widely expressed multifunctional cytoplasmic protein that is able to noncovalently bind ubiquitin and several signaling proteins, suggesting a regulatory role connected to the ubiquitin-proteasome pathway. It functions as a scaffolding protein that regulates a diverse range of signaling pathways leading to activation of the nuclear factor kappa B (NF-kappaB) family of transcription factors. It also plays a novel role in connecting receptor signals with the endosomal signaling network required for mediating TrkA-induced differentiation. SQSTM contains a PB1 dimerization domain, a tumor necrosis factor receptor-associated factor 6 (TRAF6) binding site, and a C-terminal ubiquitin-associated (UBA) domain that mediates the recognition of polyubiquitin chains and ubiquitylated substrates.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|
gi 31581536 392 RLIESLSQMLSMGFSDEGGWLTRLLQTKNYDIGAALDTIQ 431
Cdd:cd14320   1 KIEEALSQMLAMGFSNEGGWLTRLLEAKNGDIGKVLDVIQ 40

PB1 domain; Phox and Bem1p domain, present in many eukaryotic cytoplasmic signalling proteins. The domain adopts a beta-grasp fold, similar to that found in ubiquitin and Ras-binding domains. A motif, variously termed OPR, PC and AID, represents the most conserved region of the majority of PB1 domains, and is necessary for PB1 domain function. This function is the formation of PB1 domain heterodimers, although not all PB1 domain pairs associate.

                           10        20        30        40        50        60        70        80
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 31581536      3 SLTVKAYLLGkeeaarEIRRFSFCfspepeaeaaaGPGPCERLLSRVAVLFPaLRPGGFQAHYRDEDGDLVAFSSDEELT 82
Cdd:smart00666   1 TVDVKLRYGG------ETRRLSVP-----------RDISFEDLRSKVAKRFG-LDNQSFTLKYQDEDGDLVSLTSDEDLE 62

                           90
                   ....*....|....*...
gi 31581536     83 MAMSYVK---DDIFRIYI 97
Cdd:smart00666  63 EAIEEYDslgSKKLRLHV 80

Zinc finger, ZZ type; Zinc finger present in dystrophin, CBP/p300. ZZ in dystrophin binds calmodulin. Putative zinc finger; binding not yet shown. Four to six cysteine residues in its sequence are responsible for coordinating zinc ions, to reinforce the structure.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|..
gi 31581536   120 HPNVICDGC-NGPVVGTRYKCSVCPDYDLCSVCEGKGLHREH 160
Cdd:pfam00569   2 HKVYTCNGCsNDPSIGVRYHCLRCSDYDLCQSCFQTHKGGNH 43

The PB1 domain is an essential part of p62 scaffold protein (alias sequestosome 1,SQSTM) involved in cell signaling, receptor internalization, and protein turnover. The PB1 domain is a modular domain mediating specific protein-protein interaction which play roles in many critical cell processes. A canonical PB1-PB1 interaction, which involves heterodimerization of two PB1 domains, is required for the formation of macromolecular signaling complexes ensuring specificity and fidelity during cellular signaling. The interaction between two PB1 domain depends on the type of PB1. There are three types of PB1 domains: type I which contains an OPCA motif, acidic aminoacid cluster, type II which contains a basic cluster, and type I/II which contains both an OPCA motif and a basic cluster. Interactions of PB1 domains with other protein domains have been described as noncanonical PB1-interactions. The PB1 domain module is conserved in amoebas, fungi, animals, and plants.

                        10        20        30        40        50        60        70        80
                ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 31581536   4 LTVKAYLLGKEeAAREIRRFSFCfspepeaeaAAGPGPCERLLSRVAVLFPALRPGGFQAHYRDEDGDLVAFSSDEELTM 83
Cdd:cd06402   1 LTVKAYLLGKD-ANAEIRRFAID---------EDVSTSYEYLVEKVAAVFPSLRGKNFQLFWKDEEGDLVAFSSDEELVM 70

                        90
                ....*....|....*..
gi 31581536  84 AMSYVKDDIFRIYIKEK 100
Cdd:cd06402  71 ALGSLNDDTFRIYIKEK 87

UBA domain of sequestosome-1 (SQSTM) and similar proteins; SQSTM, also called EBI3-associated protein of 60 kDa (EBIAP /p60), phosphotyrosine-independent ligand for the Lck SH2 domain of 62 kDa, or ubiquitin-binding protein p62, is a widely expressed multifunctional cytoplasmic protein that is able to noncovalently bind ubiquitin and several signaling proteins, suggesting a regulatory role connected to the ubiquitin-proteasome pathway. It functions as a scaffolding protein that regulates a diverse range of signaling pathways leading to activation of the nuclear factor kappa B (NF-kappaB) family of transcription factors. It also plays a novel role in connecting receptor signals with the endosomal signaling network required for mediating TrkA-induced differentiation. SQSTM contains a PB1 dimerization domain, a tumor necrosis factor receptor-associated factor 6 (TRAF6) binding site, and a C-terminal ubiquitin-associated (UBA) domain that mediates the recognition of polyubiquitin chains and ubiquitylated substrates.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|
gi 31581536 392 RLIESLSQMLSMGFSDEGGWLTRLLQTKNYDIGAALDTIQ 431
Cdd:cd14320   1 KIEEALSQMLAMGFSNEGGWLTRLLEAKNGDIGKVLDVIQ 40

Zinc finger, ZZ type. Zinc finger present in dystrophin, CBP/p300 and many other proteins. The ZZ motif coordinates one or two zinc ions and most likely participates in ligand binding or molecular scaffolding. Many proteins containing ZZ motifs have other zinc-binding motifs as well, and the majority serve as scaffolds in pathways involving acetyltransferase, protein kinase, or ubiqitin-related activity. ZZ proteins can be grouped into the following functional classes: chromatin modifying, cytoskeletal scaffolding, ubiquitin binding or conjugating, and membrane receptor or ion-channel modifying proteins.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|..
gi 31581536 123 VICDGCNGPVVGTRYKCSVCPDYDLCSVC--EGKGLH-REHS 161
Cdd:cd02249   1 YSCDGCLKPIVGVRYHCLVCEDFDLCSSCyaKGKKGHpPDHS 42

PB1 domain;

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 31581536    21 RRFSFCFSPEPEAEAAAGPG-PCERLLSRVAVLFPaLRPGGFQAHYRDEDGDLVAFSSDEELTMAMSYVK---DDIFRIY 96
Cdd:pfam00564   2 VRLKLRYGGGIRRFLSVSRGiSFEELRALVEQRFG-LDDVDFKLKYPDEDGDLVSLTSDEDLEEALEEARslgSKSLRLH 80

                  ....
gi 31581536    97 IKEK 100
Cdd:pfam00564  81 VFPT 84

Zinc finger, ZZ type. Zinc finger present in Drosophila Mind bomb (D-mib) and related proteins. The ZZ motif coordinates two zinc ions and most likely participates in ligand binding or molecular scaffolding. Mind bomb is an E3 ubiqitin ligase that has been shown to regulate signaling by the Notch ligand Delta in Drosophila melanogaster.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|
gi 31581536 123 VICDGCNG-PVVGTRYKCSVCPDYDLCSVCEGKGLHR-EH 160
Cdd:cd02339   1 IICDTCRKqGIIGIRWKCAECPNYDLCTTCYHGDKHDlEH 40

Zinc finger, ZZ type. Zinc finger present in CBP/p300 and related proteins. The ZZ motif coordinates two zinc ions and most likely participates in ligand binding or molecular scaffolding. CREB-binding protein (CBP) is a large multidomain protein that provides binding sites for transcriptional coactivators, the role of the ZZ domain in CBP/p300 is unclear.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|
gi 31581536 125 CDGCNGpVVGTRYKCSVCPDYDLCSVC-EGKGLHREHSKL 163
Cdd:cd02337   3 CNECKH-HVETRWHCTVCEDYDLCITCyNTKNHPHKMEKL 41

Zinc finger, ZZ type. Zinc finger present in ZZZ3 (ZZ finger containing 3) and related proteins. The ZZ motif coordinates two zinc ions and most likely participates in ligand binding or molecular scaffolding.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....
gi 31581536 125 CDGCN-GPVVGTRYKCSVCP--DYDLCSVC-EGKGLHREHSKLI 164
Cdd:cd02341   3 CDSCGiEPIPGTRYHCSECDdgDFDLCQDCvVKGESHQEDHWLV 46

Zinc finger, ZZ type. Zinc finger present in HERC2 and related proteins. HERC2 is a potential E3 ubiquitin protein ligase and/or guanine nucleotide exchange factor. The ZZ motif coordinates two zinc ions and most likely participates in ligand binding or molecular scaffolding.

                        10        20        30
                ....*....|....*....|....*....|
gi 31581536 123 VICDGCNG-PVVGTRYKCSVCPDYDLCSVC 151
Cdd:cd02344   1 VTCDGCQMfPINGPRFKCRNCDDFDFCENC 30

Zinc finger, ZZ type. Zinc finger present in ADA2, a putative transcriptional adaptor, and related proteins. The ZZ motif coordinates two zinc ions and most likely participates in ligand binding or molecular scaffolding.

                        10        20
                ....*....|....*....|....*...
gi 31581536 125 CDGCNGPVVGT-RYKCSVCPDYDLCSVC 151
Cdd:cd02335   3 CDYCSKDITGTiRIKCAECPDFDLCLEC 30

Zinc finger, ZZ type. Zinc finger present in dystrophin and dystrobrevin. The ZZ motif coordinates two zinc ions and most likely participates in ligand binding or molecular scaffolding. Dystrophin attaches actin filaments to an integral membrane glycoprotein complex in muscle cells. The ZZ domain in dystrophin has been shown to be essential for binding to the membrane protein beta-dystroglycan.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|..
gi 31581536 123 VICDGCNG-PVVGTRYKCSVCPDYDLCSVCEGKGLH-REHSK 162
Cdd:cd02334   1 AKCNICKEfPITGFRYRCLKCFNYDLCQSCFFSGRTsKSHKN 42