RING/Ubox like zinc-binding domain; This is a RING zinc finger domain found in parkin proteins. Parkin consists of a ubiquitin-like (Ubl) domain and a 60-amino acid linker followed by RING0 and three additional zinc finger domains characteriztic of the RBR family. This entry relates to RING1 zinc binding domain. The RING1 domain displays the C3HC4 cross-brace motif characteriztic of RING domains. The N-terminal Ubl domain binds to RING1.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 767942939  227 LIATNSRNITCITCTDVRSPVLVFQCNSRHVICLDCFHLYCVTRLNDRQFVHDPQLGYSLPCVAGCPNSLIKELHHFRIL 306
Cdd:pfam17978   1 LIKSNSRDVPCLACTDVSSPVLVFPCEDRHVICLDCFHQYCVSRLNERQFVQHPEIGYTLPCPAGCPDSLIKEVHHFRLL 80

                  ....*....
gi 767942939  307 GEEQYNRYQ 315
Cdd:pfam17978  81 GDEQYERYQ 89

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        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....
gi 767942939   3 VFVRFNSSHGFPVEVDSDTSIFQLKEVVAKRQGVPADQLRVIFAGKELRNDWTVQNCDLDQQSIVHIVQRPWRK 76
Cdd:cd01798    1 VFVRFNSSHGFPVEVDSDWSILQLKEVVAKRQGVPPDQLRIIFAGKELSDDLTLQNCDLGQQSIVHAVQGPKRK 74

Rcat domain found in parkin and similar proteins; Parkin, also called Parkinson juvenile disease protein 2, is an 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 Lys6-, Lys11-, Lys48- and Lys63-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 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 changed to RING1-BRcat (benign-catalytic)-Rcat (required-for-catalysis) recently. The RBR domain uses an auto-inhibitory mechanism to modulate ubiquitination activity, as well as a hybrid mechanism that combines aspects from both RING and HECT E3 ligase functions to facilitate the ubiquitination reaction. This model corresponds to the Rcat domain of parkin that is essential for RBR E3 ligase activity and adopts the same fold as the BRcat domain.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|....*
gi 767942939 408 ETIKKTTKPCPRCHVPVEKNGGCMHMKCPQPQCRLEWCWNCGCEWNRVCMGDHWF 462
Cdd:cd20357    1 ETIKKTTKPCPKCKVPTEKNGGCMHMKCPRPQCGLEWCWICGCEWNRDCMGDHWF 55

RING/Ubox like zinc-binding domain; This is a RING zinc finger domain found in parkin proteins. Parkin consists of a ubiquitin-like (Ubl) domain and a 60-amino acid linker followed by RING0 and three additional zinc finger domains characteriztic of the RBR family. This entry relates to RING1 zinc binding domain. The RING1 domain displays the C3HC4 cross-brace motif characteriztic of RING domains. The N-terminal Ubl domain binds to RING1.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 767942939  227 LIATNSRNITCITCTDVRSPVLVFQCNSRHVICLDCFHLYCVTRLNDRQFVHDPQLGYSLPCVAGCPNSLIKELHHFRIL 306
Cdd:pfam17978   1 LIKSNSRDVPCLACTDVSSPVLVFPCEDRHVICLDCFHQYCVSRLNERQFVQHPEIGYTLPCPAGCPDSLIKEVHHFRLL 80

                  ....*....
gi 767942939  307 GEEQYNRYQ 315
Cdd:pfam17978  81 GDEQYERYQ 89

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        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....
gi 767942939   3 VFVRFNSSHGFPVEVDSDTSIFQLKEVVAKRQGVPADQLRVIFAGKELRNDWTVQNCDLDQQSIVHIVQRPWRK 76
Cdd:cd01798    1 VFVRFNSSHGFPVEVDSDWSILQLKEVVAKRQGVPPDQLRIIFAGKELSDDLTLQNCDLGQQSIVHAVQGPKRK 74

RING/Ubox like zinc-binding domain; This is a RING zinc finger domain found in parkin proteins. Parkin consists of a ubiquitin-like (Ubl) domain and a 60-amino acid linker followed by this domain RING0 and three additional zinc finger domains characteriztic of the RBR family. RING0 binds two coordinated zinc atoms at each extremity of the domain with a hairpin. Deletion of RING0 massively derepressed parkin activity supporting the role of RING0 in autoinhibition, point mutations in RING0 (Phe146 to Ala) or RING2 (Phe463 to Ala) both increased parkin activity. The REP (repressor element of parkin) and RING0 domains play a preeminent role in repressing parkin ligase activity through their interactions with RING1 and RING2, respectively.

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 767942939  144 SFYVYCKGPCQRVQPGKLRVQCSTCRQATLTLTQGPSCWDDVLIPNRMSGECQSPHCPGTSAEFFFKCGAHPT 216
Cdd:pfam17976   1 SFYVYCKSPCKSIQPGKLRVRCSTCKQGTLTLDRGPSCWDDVLIPNRITGVCQSPDCEGTVAEFYFKCAAHPT 73

RING finger, HC subclass, found in parkin and similar proteins; Parkin, also known as Parkinson juvenile disease protein 2, is an 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 protect 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 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 uses 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. This model corresponds to the RING domain, a C3HC4-type RING-HC finger required for RBR-mediated ubiquitination.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|....*....
gi 767942939 235 ITCITCTDVRSPVLVFQCNSRHVICLDCFHLYCVTRLNDRQFVHDPQLGYSLPCVAGCP 293
Cdd:cd16627    1 VPCITCTDVRSPVLVFPCESRHVICLDCFHLYCVTRLNDRQFVHDPQLGYTLPCPAGCE 59

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 767942939     1 MIVFVRFNSSHGFPVEVDSDTSIFQLKEVVAKRQGVPADQLRVIFAGKELRNDWTVQNCDLDQQSIVHIVQR 72
Cdd:smart00213   1 IELTVKTLDGKTITLEVKPSDTVSELKEKIAELTGIPPEQQRLIYKGKVLEDDRTLADYGIQDGSTIHLVLR 72

ubiquitin; Provisional

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|...
gi 767942939  18 DSDTSIFQLKEVVAKRQGVPADQLRVIFAGKELRNDWTVQNCDLDQQSIVHIV 70
Cdd:PTZ00044  18 EPDNTVQQVKMALQEKEGIDVKQIRLIYSGKQMSDDLKLSDYKVVPGSTIHMV 70

UV excision repair protein Rad23; All proteins in this family for which functions are known are components of a multiprotein complex used for targeting nucleotide excision repair to specific parts of the genome. In humans, Rad23 complexes with the XPC protein. This family is based on the phylogenomic analysis of JA Eisen (1999, Ph.D. Thesis, Stanford University). [DNA metabolism, DNA replication, recombination, and repair]

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 767942939    2 IVFVRFNSSHgFPVEVDSDTSIFQLKEVVAKRQGV---PADQLRVIFAGKELRNDWTVQNCDLDQQS-IVHIVQRP 73
Cdd:TIGR00601   3 LTFKTLQQQK-FKIDMEPDETVKELKEKIEAEQGKdayPVAQQKLIYSGKILSDDKTVKEYKIKEKDfVVVMVSKP 77

RING/Ubox like zinc-binding domain; This is a RING zinc finger domain found in parkin proteins. Parkin consists of a ubiquitin-like (Ubl) domain and a 60-amino acid linker followed by RING0 and three additional zinc finger domains characteriztic of the RBR family. This entry relates to RING1 zinc binding domain. The RING1 domain displays the C3HC4 cross-brace motif characteriztic of RING domains. The N-terminal Ubl domain binds to RING1.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 767942939  227 LIATNSRNITCITCTDVRSPVLVFQCNSRHVICLDCFHLYCVTRLNDRQFVHDPQLGYSLPCVAGCPNSLIKELHHFRIL 306
Cdd:pfam17978   1 LIKSNSRDVPCLACTDVSSPVLVFPCEDRHVICLDCFHQYCVSRLNERQFVQHPEIGYTLPCPAGCPDSLIKEVHHFRLL 80

                  ....*....
gi 767942939  307 GEEQYNRYQ 315
Cdd:pfam17978  81 GDEQYERYQ 89

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        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....
gi 767942939   3 VFVRFNSSHGFPVEVDSDTSIFQLKEVVAKRQGVPADQLRVIFAGKELRNDWTVQNCDLDQQSIVHIVQRPWRK 76
Cdd:cd01798    1 VFVRFNSSHGFPVEVDSDWSILQLKEVVAKRQGVPPDQLRIIFAGKELSDDLTLQNCDLGQQSIVHAVQGPKRK 74

RING/Ubox like zinc-binding domain; This is a RING zinc finger domain found in parkin proteins. Parkin consists of a ubiquitin-like (Ubl) domain and a 60-amino acid linker followed by this domain RING0 and three additional zinc finger domains characteriztic of the RBR family. RING0 binds two coordinated zinc atoms at each extremity of the domain with a hairpin. Deletion of RING0 massively derepressed parkin activity supporting the role of RING0 in autoinhibition, point mutations in RING0 (Phe146 to Ala) or RING2 (Phe463 to Ala) both increased parkin activity. The REP (repressor element of parkin) and RING0 domains play a preeminent role in repressing parkin ligase activity through their interactions with RING1 and RING2, respectively.

                          10        20        30        40        50        60        70
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 767942939  144 SFYVYCKGPCQRVQPGKLRVQCSTCRQATLTLTQGPSCWDDVLIPNRMSGECQSPHCPGTSAEFFFKCGAHPT 216
Cdd:pfam17976   1 SFYVYCKSPCKSIQPGKLRVRCSTCKQGTLTLDRGPSCWDDVLIPNRITGVCQSPDCEGTVAEFYFKCAAHPT 73

RING finger, HC subclass, found in parkin and similar proteins; Parkin, also known as Parkinson juvenile disease protein 2, is an 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 protect 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 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 uses 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. This model corresponds to the RING domain, a C3HC4-type RING-HC finger required for RBR-mediated ubiquitination.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|....*....
gi 767942939 235 ITCITCTDVRSPVLVFQCNSRHVICLDCFHLYCVTRLNDRQFVHDPQLGYSLPCVAGCP 293
Cdd:cd16627    1 VPCITCTDVRSPVLVFPCESRHVICLDCFHLYCVTRLNDRQFVHDPQLGYTLPCPAGCE 59

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.

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 767942939   3 VFVRFNSSHGFPVEVDSDTSIFQLKEVVAKRQGVPADQLRVIFAGKELRNDWTVQNCDLDQQSIVHIV 70
Cdd:cd17039    1 ITVKTLDGKTYTVEVDPDDTVADLKEKIEEKTGIPVEQQRLIYNGKELKDDKTLSDYGIKDGSTIHLV 68

Rcat (required-for-catalysis) domain, part of the RBR (RING1-BRcat-Rcat) domain; The RBR family of RING-type E3 ligases are characterized by containing an RBR domain, which was previously known as RING-BetweenRING-RING domain or TRIAD [two RING fingers and a DRIL (double RING finger linked)] domain. It is composed of an extended RING domain (RING1) followed by an in-between RING (IBR) domain and the catalytic domain, which is structurally an IBR domain but is commonly designated RING2. Based on current understanding of the structural biology of RBR ligases, the nomenclature of RBR has been changed to RING1-BRcat (benign-catalytic)-Rcat (required-for-catalysis) recently, where the IBR and RING2 domains have been renamed as BRcat and Rcat domains, respectively. The RBR domain uses an auto-inhibitory mechanism to modulate ubiquitination activity, as well as a hybrid mechanism that combines aspects from both RING and HECT E3 ligase functions to facilitate the ubiquitination reaction. The Rcat domain contains the catalytic cysteine residue and ubiquitination activity. RBR family members play roles in protein quality control and can indirectly regulate transcription. Evidence suggests that RBR proteins are often parts of cullin-containing ubiquitin ligase complexes. This model corresponds to the Rcat domain that adopts the same fold as the BRcat domain.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|
gi 767942939 413 TTKPCPRCHVPVEKNGGCMHMKCpqPQCRLEWCWNCGCEW 452
Cdd:cd20336    1 NTKKCPKCKVPIEKNGGCNHMTC--SRCGTEFCWLCGKPW 38

Rcat domain found in E3 ubiquitin-protein ligase ARI7 and similar proteins; This subfamily contains probable RBR-type E3 ubiquitin-protein ligases (EC 2.3.2.31) including Arabidopsis thaliana ARI5, ARI6, ARI7, and ARI8, as well as Dictyostelium discoideum RbrA (also called Ariadne-like ubiquitin ligase). They may function as part of E3 complexes, which accept ubiquitin from E2 ubiquitin-conjugating enzymes and then transfer it to substrates. RbrA may be required for normal cell-type proportioning and cell sorting during multicellular development, and is also necessary for spore cell viability. Members of this subfamily contain an 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 changed to RING1-BRcat (benign-catalytic)-Rcat (required-for-catalysis) recently. The RBR domain uses an auto-inhibitory mechanism to modulate ubiquitination activity, as well as a hybrid mechanism that combines aspects from both RING and HECT E3 ligase functions to facilitate the ubiquitination reaction. This model corresponds to the Rcat domain of ARI7-like proteins that are essential for RBR E3 ligase activity and adopt the same fold as the BRcat domain.

                         10        20        30
                 ....*....|....*....|....*....|....*....
gi 767942939 414 TKPCPRCHVPVEKNGGCMHMKCpQPQCRLEWCWNCGCEW 452
Cdd:cd22583    2 TKPCPKCKRPIEKNQGCMHMTC-SPPCKHEFCWLCLGPW 39

Rcat domain found in two RING fingers and DRIL [double RING finger linked] 1 (TRIAD1); TRIAD1, also called ariadne-2 (ARI-2), protein ariadne-2 homolog, Ariadne RBR E3 ubiquitin protein ligase 2 (ARIH2), or UbcM4-interacting protein 48, is an RBR-type E3 ubiquitin-protein ligase that catalyzes the formation of polyubiquitin chains linked via lysine-48 as well as lysine-63 residues. Its auto-ubiquitylation can be catalyzed by the E2 conjugating enzyme UBCH7. TRIAD1 has been implicated in hematopoiesis, specifically in myelopoiesis, as well as in embryogenesis. It functions as a regulator of endosomal transport, and is required for the proper function of multivesicular bodies. It also acts as a novel ubiquitination target for proteasome-dependent degradation by murine double minute 2 (MDM2). As a proapoptotic protein, TRIAD1 promotes p53 activation, and inhibits MDM2-mediated p53 ubiquitination and degradation. Furthermore, TRIAD1 can inhibit the ubiquitination and proteasomal degradation of growth factor independence 1 (Gfi1), a transcriptional repressor essential for the function and development of many different hematopoietic lineages. TRIAD1 contains an 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 changed to RING1-BRcat (benign-catalytic)-Rcat (required-for-catalysis) recently. The RBR domain uses an auto-inhibitory mechanism to modulate ubiquitination activity, as well as a hybrid mechanism that combines aspects from both RING and HECT E3 ligase functions to facilitate the ubiquitination reaction. This model corresponds to the Rcat domain of TRIAD1 that is essential for RBR E3 ligase activity and adopts the same fold as the BRcat domain.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|
gi 767942939 414 TKPCPRCHVPVEKNGGCMHMKCpqPQCRLEWCWNCGCEWN 453
Cdd:cd20360    3 TKDCPKCHVCIEKNGGCNHMQC--SKCKHEFCWMCLGDWK 40

Rcat domain found in RING finger protein 14 (RNF14); RNF14, also called androgen receptor (AR)-associated protein 54 (ARA54), HFB30, or Triad2 protein, is an RBR-type E3 ubiquitin-protein ligase that is highly expressed in the testis and interacts with class III E2s (UBE2E2, UbcH6, and UBE2E3). Its differential localization may play an important role in testicular development and spermatogenesis in humans. RNF14 functions as a transcriptional regulator of mitochondrial and immune function in muscles. It is a ligand-dependent AR co-activator that enhances AR-dependent transcriptional activation. It also may participate in enhancing cell cycle progression and cell proliferation via induction of cyclin D1. Moreover, RNF14 is crucial for colon cancer cell survival. It acts as a new enhancer of the Wnt-dependent transcriptional outputs that acts at the level of the T-cell factor/lymphoid enhancer factor (TCF/LEF)-beta-catenin complex. RNF14 contains an N-terminal RWD domain, and a C-terminal RBR domain. The RBR domain 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 changed to RING1-BRcat (benign-catalytic)-Rcat (required-for-catalysis) recently. The RBR domain uses an auto-inhibitory mechanism to modulate ubiquitination activity, as well as a hybrid mechanism that combines aspects from both RING and HECT E3 ligase functions to facilitate the ubiquitination reaction. This model corresponds to the Rcat domain of RNF14 that is essential for RBR E3 ligase activity and adopts the same fold as the BRcat domain.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|....*..
gi 767942939 403 EAASKETIKKTTKPCPRCHVPVEKNGGCMHMKCpqPQCRLEWCWNCG 449
Cdd:cd20354    2 EKLSEEWLEKNSKPCPGCGTLIEKIDGCNKMTC--TKCRTYFCWLCL 46

Rcat domain found in ankyrin repeat and IBR domain-containing protein 1 (ANKIB1) and similar proteins; ANKIB1 is an RBR-type E3 ubiquitin-protein ligase that may function as part of an E3 complex, which accepts ubiquitin from specific E2 ubiquitin-conjugating enzymes and then transfers it to substrates. It contains N-terminal ankyrin repeats, and an 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 changed to RING1-BRcat (benign-catalytic)-Rcat (required-for-catalysis) recently. The RBR domain uses an auto-inhibitory mechanism to modulate ubiquitination activity, as well as a hybrid mechanism that combines aspects from both RING and HECT E3 ligase functions to facilitate the ubiquitination reaction. This model corresponds to the Rcat domain of ANKIB1 that is essential for RBR E3 ligase activity and adopts the same fold as the BRcat domain.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|....*
gi 767942939 410 IKKTTKPCPRCHVPVEKNGGCMHMKCpqPQCRLEWCWNCGCEWNR 454
Cdd:cd20361    5 LVTNSKPCPNCKSPIQKNEGCNHMKC--SKCKYDFCWVCLEEWKK 47

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.

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                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 767942939   1 MIVFVRFNSSHGFPVEVDSDTSIFQLKEVVAKRQGVPADQLRVIFAGKELRNDWTVQNCDLDQQSIVHIVQR 72
Cdd:cd01803    1 MQIFVKTLTGKTITLEVEPSDTIENVKAKIQDKEGIPPDQQRLIFAGKQLEDGRTLSDYNIQKESTLHLVLR 72

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 767942939  15 VEVDSDTSIFQLKEVVAKRQGVPADQLRVIFAGKELRNDWTVQNCDLDQQSIVHIV 70
Cdd:cd01808   16 FEVPEDSSVKEFKEEISKKFKAPVEQLVLIFAGKILKDQDTLSQHGIKDGLTVHLV 71

In Between Ring fingers; the domains occurs between pairs og RING fingers

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                   ....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 767942939   312 NRYQQYGAEECVLQMGG-VLCPRPGCGAGLL--PEPDQRKVTCEGgnglgCGFAFCRECKEAYHEG 374
Cdd:smart00647   1 EKYERLLLESYVESNPDlKWCPAPDCSAAIIvtEEEGCNRVTCPK-----CGFSFCFRCKVPWHSP 61

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.

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                 ....*....|....*....|....*....|....*....|....*....|....*.
gi 767942939  17 VDSDTSIFQLKEVVAKRQGVPADQLRVIFAGKELRNDWTVQNCDLDQQsIVHIVQR 72
Cdd:cd01809   17 VPEEITVKEFKEHIASSVNIPAEKQRLIFQGRVLQDDKKLKEYDVDGK-VIHLVER 71

BRcat domain found in RING finger protein 14 (RNF14); RNF14, also called androgen receptor (AR)-associated protein 54 (ARA54), HFB30, or Triad2 protein, is an RBR-type E3 ubiquitin-protein ligase that is highly expressed in the testis and interacts with class III E2s (UBE2E2, UbcH6, and UBE2E3). Its differential localization may play an important role in testicular development and spermatogenesis in humans. RNF14 functions as a transcriptional regulator of mitochondrial and immune function in muscles. It is a ligand-dependent AR co-activator that enhances AR-dependent transcriptional activation. It may also participate in enhancing cell cycle progression and cell proliferation via induction of cyclin D1. Moreover, RNF14 is crucial for colon cancer cell survival. It acts as a new enhancer of the Wnt-dependent transcriptional outputs that acts at the level of the T-cell factor/lymphoid enhancer factor (TCF/LEF)-beta-catenin complex. RNF14 contains an N-terminal RWD domain, and a C-terminal RBR domain. The RBR domain 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 changed to RING1-BRcat (benign-catalytic)-Rcat (required-for-catalysis) recently. The RBR domain uses 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. This model corresponds to the BRcat domain of RNF14 that adopts the same fold as the Rcat domain while lacking the catalytic cysteine residue and ubiquitination activity.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|....*..
gi 767942939 329 VLCPRPGCGAGLLPEPDQRKVTCeggngLGCGFAFCRECKEAYHEGE 375
Cdd:cd20341    8 VYCPRPSCQTPVILEPDENLGIC-----PSCNYAFCTLCRETYHGVS 49

Rcat domain found in cullin-9 (CUL-9) and similar proteins; CUL-9, also called UbcH7-associated protein 1 (H7-AP1), p53-associated parkin-like cytoplasmic protein, or PARC, is a cytoplasmic RBR-type E3 ubiquitin-protein ligase that function as a tumor suppressor and promotes p53-dependent apoptosis. It mediates the ubiquitination and degradation of cytosolic cytochrome c to promote survival in neurons and cancer cells. It is also a critical downstream effector of the 3M complex in the maintenance of microtubules and genome integrity. Moreover, CUL-9, together with CUL-7, forms homodimers and heterodimers, as well as some atypical cullin RING ligase complexes, which may exhibit ubiquitin ligase activity. CUL-9 contains a CPH domain (conserved in Cul7, PARC, and HERC2 proteins), a DOC (DOC1/APC10) domain, cullin homology domains linked with E3 ligase function, and a C-terminal RBR domain 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 changed to RING1-BRcat (benign-catalytic)-Rcat (required-for-catalysis) recently. The RBR domain uses an auto-inhibitory mechanism to modulate ubiquitination activity, as well as a hybrid mechanism that combines aspects from both RING and HECT E3 ligase functions to facilitate the ubiquitination reaction. This model corresponds to the Rcat domain of CUL-9 that is essential for RBR E3 ligase activity and adopts the same fold as the BRcat domain.

                         10        20        30
                 ....*....|....*....|....*....|....*....
gi 767942939 414 TKPCPRCHVPVEKNGGCMHMKCpqPQCRLEWCWNCGCEW 452
Cdd:cd20359    7 SKRCPSCQAQIEKNEGCLHMTC--AKCNHGFCWRCLKPW 43

Rcat domain found in the RNF144 protein subfamily; The RNF144 subfamily includes RNF144A and RNF144B, which are transmembrane (TM) domain-containing RBR-type E3 ubiquitin-protein ligases. RNF144A, also called UbcM4-interacting protein 4 (UIP4), or ubiquitin-conjugating enzyme 7-interacting protein 4, targets DNA-dependent protein kinase catalytic subunit (DNA-PKcs), and thus promotes DNA damage-induced cell apoptosis. It is transcriptionally repressed by metastasis-associated protein 1 (MTA1) and inhibits MTA1-driven cancer cell migration and invasion. RNF144B, also called PIR2, IBR domain-containing protein 2 (IBRDC2), or p53-inducible RING finger protein (p53RFP), induces p53-dependent but caspase-independent apoptosis. It interacts with E2 ubiquitin-conjugating enzymes UbcH7 and UbcH8, but not with UbcH5. It is involved in ubiquitination and degradation of p21, a p53 downstream protein promoting growth arrest and antagonizing apoptosis, suggesting a role in switching a cell from p53-mediated growth arrest to apoptosis. Moreover, RNF144B regulates the levels of Bax, a pro-apoptotic protein from the Bcl-2 family, and protects cells from unprompted Bax activation and cell death. It also regulates epithelial homeostasis by mediating degradation of p21WAF1 and p63. Both RNF144A and RNF144B contain an RBR domain followed by a potential single-TM domain. The RBR domain 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 changed to RING1-BRcat (benign-catalytic)-Rcat (required-for-catalysis) recently. The RBR domain uses an auto-inhibitory mechanism to modulate ubiquitination activity, as well as a hybrid mechanism that combines aspects from both RING and HECT E3 ligase functions to facilitate the ubiquitination reaction. This model corresponds to the Rcat domain of the RNF144 protein subfamily that is essential for RBR E3 ligase activity and adopts the same fold as the BRcat domain.

                         10        20        30
                 ....*....|....*....|....*....|....
gi 767942939 415 KPCPRCHVPVEKNGGCMHMKCpqPQCRLEWCWNC 448
Cdd:cd20352    6 KRCPMCHVPIERDEGCAQMMC--KNCKHVFCWYC 37

Rcat domain of ATP-dependent RNA helicase DEAH12 and similar proteins; This group includes Arabidopsis thaliana ATP-dependent RNA helicases DEAH11 and DEAH12, which may be bifunctional proteins that function as DEAD-box RNA helicases (EC 3.6.4.13) and RBR-type E3 ubiquitin-protein ligases (EC 2.3.2.31). As RNA helicases, they may utilize the energy from ATP hydrolysis to unwind RNA (or DNA). DEAD-box RNA helicases participate in every aspect of RNA metabolism. As E3 ubiquitin-protein ligase, they may function as part of E3 complexes, which accept ubiquitin from specific E2 ubiquitin-conjugating enzymes and then transfer it to substrates. Other members of this group may not have an RNA helicase domain. All members contain an 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 changed to RING1-BRcat (benign-catalytic)-Rcat (required-for-catalysis) recently. The RBR domain uses an auto-inhibitory mechanism to modulate ubiquitination activity, as well as a hybrid mechanism that combines aspects from both RING and HECT E3 ligase functions to facilitate the ubiquitination reaction. This model corresponds to the Rcat domain that is essential for RBR E3 ligase activity and adopts the same fold as the BRcat domain.

                         10        20        30
                 ....*....|....*....|....*....|....
gi 767942939 415 KPCPRCHVPVEKNGGCMHMKCpqPQCRLEWCWNC 448
Cdd:cd22585    3 KRCPKCKSLIEKIDGCNHVTC--TRCGTHICWVC 34

UV excision repair protein Rad23; All proteins in this family for which functions are known are components of a multiprotein complex used for targeting nucleotide excision repair to specific parts of the genome. In humans, Rad23 complexes with the XPC protein. This family is based on the phylogenomic analysis of JA Eisen (1999, Ph.D. Thesis, Stanford University). [DNA metabolism, DNA replication, recombination, and repair]

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                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 767942939    2 IVFVRFNSSHgFPVEVDSDTSIFQLKEVVAKRQGV---PADQLRVIFAGKELRNDWTVQNCDLDQQS-IVHIVQRP 73
Cdd:TIGR00601   3 LTFKTLQQQK-FKIDMEPDETVKELKEKIEAEQGKdayPVAQQKLIYSGKILSDDKTVKEYKIKEKDfVVVMVSKP 77

ubiquitin-like (Ubl) domain found in small ubiquitin-related modifier 1 (SUMO-1) and similar proteins; SUMO (also known as "Smt3" and "sentrin" in other organisms) resembles ubiquitin (Ub) in structure, ligation to other proteins and the mechanism of ligation. 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 Ub and the epsilon-amino group of a substrate lysine. SUMOs, like Ub, are covalently conjugated to lysine residues in a wide variety of target proteins in eukaryotic cells and regulate numerous cellular processes, such as transcription, epigenetic gene control, genomic instability, and protein degradation. Four SUMO paralogs exist in mammals, SUMO1 through SUMO4. SUMO2-SUMO4 are more closely related to each other than they are to SUMO1. SUMO1 is a binding partner of the RAD51/52 nucleoprotein filament proteins, which mediate DNA strand exchange. SUMO1 conjugation to cellular proteins has been implicated in multiple important cellular processes, such as nuclear transport, cell cycle control, oncogenesis, inflammation, and the response to virus infection.

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                 ....*....|....*....|....*....|....*....|....*....|....*
gi 767942939  17 VDSDTSIFQLKEVVAKRQGVPADQLRVIFAGKELRNDWTVQNCDLDQQSIVHIVQ 71
Cdd:cd16114   18 VKMTTHLKKLKESYCQRQGVPMNSLRFLFEGQRINDNHTPKELGMEEEDVIEVYQ 72

BRcat domain found in human homolog of Drosophila Ariadne (HHARI) and similar proteins; This subfamily includes Drosophila melanogaster protein ariadne-1 (ARI-1), and its eukaryotic homologs, such as HHARI. ARI-1 is a widely expressed Drosophila RING-finger protein that localizes mainly in the cytoplasm, and is required for neural development. It interacts with the ubiquitin-conjugating enzyme, UbcD10. HHARI is also called H7-AP2, monocyte protein 6 (MOP-6), protein ariadne-1 homolog, Ariadne RBR E3 ubiquitin protein ligase 1 (ARIH1), ariadne-1 (ARI-1), UbcH7-binding protein, UbcM4-interacting protein, or ubiquitin-conjugating enzyme E2-binding protein 1. It is an RBR-type E3 ubiquitin-protein ligase highly expressed in nuclei, where it is co-localized with nuclear bodies including Cajal, PML, and Lewy bodies. It interacts with the E2 conjugating enzymes UbcH7, UbcH8, UbcM4, and UbcD10 in human, mouse and fly, and modulates the ubiquitylation of substrate proteins including single-minded 2 (SIM2) and translation initiation factor 4E homologous protein (4EHP). It functions as a potent mediator of DNA damage-induced translation arrest, which protects stem and cancer cells against genotoxic stress by initiating a 4EHP-mediated mRNA translation arrest. HHARI contains an 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 changed to RING1-BRcat (benign-catalytic)-Rcat (required-for-catalysis) recently. The RBR domain uses an auto-inhibitory mechanism to modulate ubiquitination activity, as well as a hybrid mechanism that combines aspects from both RING and HECT E3 ligase functions to facilitate the ubiquitination reaction. This model corresponds to the BRcat domain of HHARI and similar proteins that adopt the same fold as the Rcat domain while lacking the catalytic cysteine residue and ubiquitination activity.

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                 ....*....|....*....|....*....|....*....|....
gi 767942939 331 CPRPGCG-AGLLPEPDQRKVTCEggnglgCGFAFCRECKEAYHE 373
Cdd:cd20343   26 CPAPDCGhAVKVQYPDARPVTCK------CGHTFCFACGENWHE 63

Rcat domain found in RING finger protein 144B (RNF144B); RNF144B, also called PIR2, IBR domain-containing protein 2 (IBRDC2), or p53-inducible RING finger protein (p53RFP), is a transmembrane (TM) domain-containing RBR E3 ubiquitin-protein ligase that induces p53-dependent but caspase-independent apoptosis. It interacts with E2 ubiquitin-conjugating enzymes UbcH7 and UbcH8, but not with UbcH5. It is involved in ubiquitination and degradation of p21, a p53 downstream protein promoting growth arrest and antagonizing apoptosis, suggesting a role in switching a cell from p53-mediated growth arrest to apoptosis. Moreover, RNF144B regulates the levels of Bax, a pro-apoptotic protein from the Bcl-2 family, and protects cells from unprompted Bax activation and cell death. It also regulates epithelial homeostasis by mediating degradation of p21WAF1 and p63. RNF144B contains an RBR domain followed by a potential single-TM domain. The RBR domain 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 changed to RING1-BRcat (benign-catalytic)-Rcat (required-for-catalysis) recently. The RBR domain uses an auto-inhibitory mechanism to modulate ubiquitination activity, as well as a hybrid mechanism that combines aspects from both RING and HECT E3 ligase functions to facilitate the ubiquitination reaction. This model corresponds to the Rcat domain of RNF144B that is essential for RBR E3 ligase activity and adopts the same fold as the BRcat domain.

                         10        20        30
                 ....*....|....*....|....*....|....
gi 767942939 415 KPCPRCHVPVEKNGGCMHMKCpqPQCRLEWCWNC 448
Cdd:cd20369    7 KQCPVCRVYIERNEGCAQMMC--KNCKHTFCWYC 38

IBR domain, a half RING-finger domain; The IBR (In Between Ring fingers) domain is often found to occur between pairs of ring fingers (pfam00097). This domain has also been called the C6HC domain and DRIL (for double RING finger linked) domain. Proteins that contain two Ring fingers and an IBR domain (these proteins are also termed RBR family proteins) are thought to exist in all eukaryotic organizms. RBR family members play roles in protein quality control and can indirectly regulate transcription. Evidence suggests that RBR proteins are often parts of cullin-containing ubiquitin ligase complexes. The ubiquitin ligase Parkin is an RBR family protein whose mutations are involved in forms of familial Parkinson's disease.

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                  ....*....|....*....|....*....|....*....|....*..
gi 767942939  411 KKTTKPCPR--CHVPVEKNGGCM---HMKCPQpqCRLEWCWNCGCEW 452
Cdd:pfam01485  15 DPNLKWCPTpdCGYIIELTDGCSntsHVTCSK--CGHEFCFNCKEEW 59