PNGase/UBA or UBX (PUB) domain of p97 adaptor proteins; The PUB domain is found in p97 adaptor proteins such as PNGase, UBXD1 (UBX domain-containing protein 1), and RNF31 (RING finger protein 31). It functions as a p97 (also known as valosin-containing protein or VCP) adaptor by interacting with the D1 and/or D2 ATPase domains. The p97, a type II AAA+ ATPase, is involved in a variety of cellular processes such as the deglycosylation of ERAD substrates, membrane fusion, transcription factor activation and cell cycle regulation through differential binding to specific adaptor proteins. The PUB domain in UBX-domain protein 1 (UBXD1), which is widely expressed in higher eukaryotes (except for fungi) and which is involved in substrate recruitment to p97, interacts strongly with the C-terminus of p97. Peptide:N-glycanase (PNGase), a deglycosylating enzyme that functions in proteasome-dependent degradation of misfolded glycoproteins which are translocated from the endoplasmic reticulum (ER) to the cytosol during ERAD, associates with the ubiquitin-proteasome system proteins mediated by the N-terminal PUB domain. PNGase is present in all eukaryotic organisms; however, the yeast PNGase ortholog does not contain the PUB domain. The RNF31 protein, also known as HOIP or Zibra, contains an N-terminal PUB domain similar to those in PNGase and UBXD1, suggesting its association with p97.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 40254409   51 DAGRLVRCNAHGEPRnYLNTLSTALNILEKYGRNLLSPQRPRYWRSVKFNNPVFRSTVDAVQGGRDVLRLYGYTEERPDG 130
Cdd:cd10464    1 NFARLLRLNQHVNNQ-FLNKLVTALNILEKYGRNLLSPGRPKFWRSVKFSNPVFRTKVDAVQGGRNVLSLYGYTESQPDG 79

                         90       100
                 ....*....|....*....|..
gi 40254409  131 LSFPEGQEEPDEYQVAVVTLEV 152
Cdd:cd10464   80 LSFPDDVEEPDISKVAKVTLDL 101

BRcat domain found in HOIL-1-interacting protein (HOIP) and similar proteins; HOIP, also called RING finger protein 31 (RNF31) or zinc in-between-RING-finger ubiquitin-associated domain protein, together with HOIL-1 and SHARPIN, forms the E3-ligase complex (also known as linear-ubiquitin-chain assembly complex LUBAC) that regulates NF-kappaB activity and apoptosis. It also interacts with the atypical mammalian orphan receptor DAX-1, trigger DAX-1 ubiquitination and stabilization, and participate in repressing steroidogenic gene expression. HOIP contains three Npl4 zinc fingers, a central ubiquitin-associated (UBA) domain responsible for interaction with the N-terminal ubiquitin-like domain (UBL) of HOIL-1L, an RBR domain, and a C-terminal linear chain determining domain (LDD). 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 BRcat domain of HOIP and similar proteins that adopt the same fold as the Rcat domain while lacking the catalytic cysteine residue and ubiquitination activity.

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 40254409  769 PDAYALFHKKLTEAVLMRDPKFLWCAQCSFGFIYEREQLEATCPQCHQTFCVRCKRQWEEQHRGRSCEDFQNWKRTND 846
Cdd:cd20337    1 PDVYELFQKKLRDRNLMKDPNFRWCAHCSFGFIYEPEQLKMQCPQCGKVTCFKCKKPWEDQHEGISCEQFQEWKREND 78

PNGase/UBA- or UBX-containing domain; This is a PUB domain (PNGase/UBA- or UBX-containing domain), found in E3 ubiquitin-protein ligase RNF31, also known as Ring finger protein 31 and HOIL-1-interacting protein (HOIP) (EC:2.3.2.27). RNF31/HOIP is observed to contribute to inborn human immunity disorders, in which RNF31/HOIP missense mutation at PUB domain gives rise to the de-stabilized LUBAC complex (linear ubiquitin chain assembly complex) and subsequently causes the auto-inflammation and immunodeficiency. In addition, RNF31 is reported to modify ERK and JNK pathways leading to cisplatin resistance. Functional studies indicate that HOIP and OTULIN interact and act as a bimolecular editing pair for linear ubiquitin signals where the HOIP-PUB domain binds to the PUB interacting motif (PIM) of OTULIN and the chaperone VCP/p9. This interaction plays an important role where the HOIP binding to OTULIN is required for the recruitment of OTULIN to the TNF receptor complex and to counteract HOIP-dependent activation of the NF-KB pathway.

                           10        20        30        40        50        60
                   ....*....|....*....|....*....|....*....|....*....|....*....|....
gi 40254409      1 MPGDEERGFLAAREELASALRWDSAQVFPLEQLMPLLATSLPPAARYLQLDAGRLVRCNAHGEP 64
Cdd:pfam18486    1 GLQEEERAFLAAREELVSALRKDPGQSFSPEQLRPLLDNSLPLATRYPKLDASRLVRSNAQGEP 64

B-box-type 1 zinc finger found in HOIL-1-interacting protein (HOIP) and similar proteins; HOIP, also termed RING finger protein 31 (RNF31), or zinc in-between-RING-finger ubiquitin-associated domain protein, together with HOIL-1 and SHARPIN, forms the E3-ligase complex (also known as linear-ubiquitin-chain assembly complex LUBAC) that regulates NF-kappaB activity and apoptosis. It also interacts with the atypical mammalian orphan receptor DAX-1, trigger DAX-1 ubiquitination and stabilization, and participate in repressing steroidogenic gene expression. HOIP contains a B-box motif that shows high sequence similarity with B-Box-type 1 zinc finger found in tripartite motif-containing proteins (TRIMs). The type 1 B-box (Bbox1) zinc finger is characterized by a C6H2 zinc-binding consensus motif.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|..
gi 40254409  214 CFLCGSAPGTLHCPACNQVSCPACDILFHGHPSRAHHLRQAL 255
Cdd:cd19815    2 CDLCGEAAASVFCASCEDKLCLSCDDLYHKHPARRSHHRQPI 43

PNGase/UBA or UBX (PUB) domain of the RNF31 (or HOIP) protein; This PUB domain is found in the p97 adaptor protein RNF31 (RING finger protein 31). The PUB domain functions as a p97 (also known as valosin-containing protein or VCP) adaptor by interacting with the D1 and/or D2 ATPase domains. The type II AAA+ ATPase p97 is involved in a variety of cellular processes such as the deglycosylation of ERAD substrates, membrane fusion, transcription factor activation and cell cycle regulation through differential binding to specific adaptor proteins. The RNF31 protein, also known as HOIP or Zibra, contains an N-terminal PUB domain similar to those in PNGase and UBXD1, suggesting its association with p97. RNF31 functions in a complex with another RING-finger protein (HOIL-IL), displaying E3 ubiquitin-protein ligase activity, and forming linear ubiquitin chain assembly complex (LUBAC) through linkages between the N- and C-termini of ubiquitin. LUBAC has been shown to activate the NF-kappaB pathway.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 40254409   51 DAGRLVRCNAHGEPRnYLNTLSTALNILEKYGRNLLSPQRPRYWRSVKFNNPVFRSTVDAVQGGRDVLRLYGYTEERPDG 130
Cdd:cd10464    1 NFARLLRLNQHVNNQ-FLNKLVTALNILEKYGRNLLSPGRPKFWRSVKFSNPVFRTKVDAVQGGRNVLSLYGYTESQPDG 79

                         90       100
                 ....*....|....*....|..
gi 40254409  131 LSFPEGQEEPDEYQVAVVTLEV 152
Cdd:cd10464   80 LSFPDDVEEPDISKVAKVTLDL 101

BRcat domain found in HOIL-1-interacting protein (HOIP) and similar proteins; HOIP, also called RING finger protein 31 (RNF31) or zinc in-between-RING-finger ubiquitin-associated domain protein, together with HOIL-1 and SHARPIN, forms the E3-ligase complex (also known as linear-ubiquitin-chain assembly complex LUBAC) that regulates NF-kappaB activity and apoptosis. It also interacts with the atypical mammalian orphan receptor DAX-1, trigger DAX-1 ubiquitination and stabilization, and participate in repressing steroidogenic gene expression. HOIP contains three Npl4 zinc fingers, a central ubiquitin-associated (UBA) domain responsible for interaction with the N-terminal ubiquitin-like domain (UBL) of HOIL-1L, an RBR domain, and a C-terminal linear chain determining domain (LDD). 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 BRcat domain of HOIP and similar proteins that adopt the same fold as the Rcat domain while lacking the catalytic cysteine residue and ubiquitination activity.

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 40254409  769 PDAYALFHKKLTEAVLMRDPKFLWCAQCSFGFIYEREQLEATCPQCHQTFCVRCKRQWEEQHRGRSCEDFQNWKRTND 846
Cdd:cd20337    1 PDVYELFQKKLRDRNLMKDPNFRWCAHCSFGFIYEPEQLKMQCPQCGKVTCFKCKKPWEDQHEGISCEQFQEWKREND 78

PNGase/UBA- or UBX-containing domain; This is a PUB domain (PNGase/UBA- or UBX-containing domain), found in E3 ubiquitin-protein ligase RNF31, also known as Ring finger protein 31 and HOIL-1-interacting protein (HOIP) (EC:2.3.2.27). RNF31/HOIP is observed to contribute to inborn human immunity disorders, in which RNF31/HOIP missense mutation at PUB domain gives rise to the de-stabilized LUBAC complex (linear ubiquitin chain assembly complex) and subsequently causes the auto-inflammation and immunodeficiency. In addition, RNF31 is reported to modify ERK and JNK pathways leading to cisplatin resistance. Functional studies indicate that HOIP and OTULIN interact and act as a bimolecular editing pair for linear ubiquitin signals where the HOIP-PUB domain binds to the PUB interacting motif (PIM) of OTULIN and the chaperone VCP/p9. This interaction plays an important role where the HOIP binding to OTULIN is required for the recruitment of OTULIN to the TNF receptor complex and to counteract HOIP-dependent activation of the NF-KB pathway.

                           10        20        30        40        50        60
                   ....*....|....*....|....*....|....*....|....*....|....*....|....
gi 40254409      1 MPGDEERGFLAAREELASALRWDSAQVFPLEQLMPLLATSLPPAARYLQLDAGRLVRCNAHGEP 64
Cdd:pfam18486    1 GLQEEERAFLAAREELVSALRKDPGQSFSPEQLRPLLDNSLPLATRYPKLDASRLVRSNAQGEP 64

Modified RING finger, HC subclass (C4C4-type), found in HOIL-1-interacting protein (HOIP) and similar proteins; HOIP, also known as RING finger protein 31 (RNF31) or zinc in-between-RING-finger ubiquitin-associated domain protein, together with HOIL-1 and SHARPIN, forms the E3-ligase complex (also known as linear-ubiquitin-chain assembly complex LUBAC) that regulates NF-kappaB activity and apoptosis. It also interacts with the atypical mammalian orphan receptor DAX-1, trigger DAX-1 ubiquitination and stabilization, and participate in repressing steroidogenic gene expression. HOIP contains three Npl4 zinc fingers, a central ubiquitin-associated (UBA) domain responsible for the interaction with the N-terminal ubiquitin-like domain (UBL) of HOIL-1L, an RBR domain, and a C-terminal linear chain determining domain (LDD). 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 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 C4C4-type RING finger motif whose overall folding is similar to that of the C3HC4-type RING-HC finger. It is required for RBR-mediated ubiquitination.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|....
gi 40254409  691 QECAVCGWALPRNRMQALISCECTICPECFRQHFTIALKEKHITDMVCPACGRP 744
Cdd:cd16631    1 QECPICFNSFPRNKMVSLTSCECKICPDCFKQYFTVVIKEKHIRDLVCPACGLP 54

B-box-type 1 zinc finger found in HOIL-1-interacting protein (HOIP) and similar proteins; HOIP, also termed RING finger protein 31 (RNF31), or zinc in-between-RING-finger ubiquitin-associated domain protein, together with HOIL-1 and SHARPIN, forms the E3-ligase complex (also known as linear-ubiquitin-chain assembly complex LUBAC) that regulates NF-kappaB activity and apoptosis. It also interacts with the atypical mammalian orphan receptor DAX-1, trigger DAX-1 ubiquitination and stabilization, and participate in repressing steroidogenic gene expression. HOIP contains a B-box motif that shows high sequence similarity with B-Box-type 1 zinc finger found in tripartite motif-containing proteins (TRIMs). The type 1 B-box (Bbox1) zinc finger is characterized by a C6H2 zinc-binding consensus motif.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|..
gi 40254409  214 CFLCGSAPGTLHCPACNQVSCPACDILFHGHPSRAHHLRQAL 255
Cdd:cd19815    2 CDLCGEAAASVFCASCEDKLCLSCDDLYHKHPARRSHHRQPI 43

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.

                           10        20        30        40        50        60
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 40254409    775 FHKKLTEAVLMRDPKFLWC--AQCSFGFIYE---REQLEATCPQCHQTFCVRCKRQWeeqHRGRSC 835
Cdd:pfam01485    3 YEKLLLKSYVESDPNLKWCptPDCGYIIELTdgcSNTSHVTCSKCGHEFCFNCKEEW---HEGLTC 65

PNGase/UBA or UBX (PUB) domain of the RNF31 (or HOIP) protein; This PUB domain is found in the p97 adaptor protein RNF31 (RING finger protein 31). The PUB domain functions as a p97 (also known as valosin-containing protein or VCP) adaptor by interacting with the D1 and/or D2 ATPase domains. The type II AAA+ ATPase p97 is involved in a variety of cellular processes such as the deglycosylation of ERAD substrates, membrane fusion, transcription factor activation and cell cycle regulation through differential binding to specific adaptor proteins. The RNF31 protein, also known as HOIP or Zibra, contains an N-terminal PUB domain similar to those in PNGase and UBXD1, suggesting its association with p97. RNF31 functions in a complex with another RING-finger protein (HOIL-IL), displaying E3 ubiquitin-protein ligase activity, and forming linear ubiquitin chain assembly complex (LUBAC) through linkages between the N- and C-termini of ubiquitin. LUBAC has been shown to activate the NF-kappaB pathway.

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 40254409   51 DAGRLVRCNAHGEPRnYLNTLSTALNILEKYGRNLLSPQRPRYWRSVKFNNPVFRSTVDAVQGGRDVLRLYGYTEERPDG 130
Cdd:cd10464    1 NFARLLRLNQHVNNQ-FLNKLVTALNILEKYGRNLLSPGRPKFWRSVKFSNPVFRTKVDAVQGGRNVLSLYGYTESQPDG 79

                         90       100
                 ....*....|....*....|..
gi 40254409  131 LSFPEGQEEPDEYQVAVVTLEV 152
Cdd:cd10464   80 LSFPDDVEEPDISKVAKVTLDL 101

BRcat domain found in HOIL-1-interacting protein (HOIP) and similar proteins; HOIP, also called RING finger protein 31 (RNF31) or zinc in-between-RING-finger ubiquitin-associated domain protein, together with HOIL-1 and SHARPIN, forms the E3-ligase complex (also known as linear-ubiquitin-chain assembly complex LUBAC) that regulates NF-kappaB activity and apoptosis. It also interacts with the atypical mammalian orphan receptor DAX-1, trigger DAX-1 ubiquitination and stabilization, and participate in repressing steroidogenic gene expression. HOIP contains three Npl4 zinc fingers, a central ubiquitin-associated (UBA) domain responsible for interaction with the N-terminal ubiquitin-like domain (UBL) of HOIL-1L, an RBR domain, and a C-terminal linear chain determining domain (LDD). 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 BRcat domain of HOIP and similar proteins that adopt the same fold as the Rcat domain while lacking the catalytic cysteine residue and ubiquitination activity.

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 40254409  769 PDAYALFHKKLTEAVLMRDPKFLWCAQCSFGFIYEREQLEATCPQCHQTFCVRCKRQWEEQHRGRSCEDFQNWKRTND 846
Cdd:cd20337    1 PDVYELFQKKLRDRNLMKDPNFRWCAHCSFGFIYEPEQLKMQCPQCGKVTCFKCKKPWEDQHEGISCEQFQEWKREND 78

PNGase/UBA- or UBX-containing domain; This is a PUB domain (PNGase/UBA- or UBX-containing domain), found in E3 ubiquitin-protein ligase RNF31, also known as Ring finger protein 31 and HOIL-1-interacting protein (HOIP) (EC:2.3.2.27). RNF31/HOIP is observed to contribute to inborn human immunity disorders, in which RNF31/HOIP missense mutation at PUB domain gives rise to the de-stabilized LUBAC complex (linear ubiquitin chain assembly complex) and subsequently causes the auto-inflammation and immunodeficiency. In addition, RNF31 is reported to modify ERK and JNK pathways leading to cisplatin resistance. Functional studies indicate that HOIP and OTULIN interact and act as a bimolecular editing pair for linear ubiquitin signals where the HOIP-PUB domain binds to the PUB interacting motif (PIM) of OTULIN and the chaperone VCP/p9. This interaction plays an important role where the HOIP binding to OTULIN is required for the recruitment of OTULIN to the TNF receptor complex and to counteract HOIP-dependent activation of the NF-KB pathway.

                           10        20        30        40        50        60
                   ....*....|....*....|....*....|....*....|....*....|....*....|....
gi 40254409      1 MPGDEERGFLAAREELASALRWDSAQVFPLEQLMPLLATSLPPAARYLQLDAGRLVRCNAHGEP 64
Cdd:pfam18486    1 GLQEEERAFLAAREELVSALRKDPGQSFSPEQLRPLLDNSLPLATRYPKLDASRLVRSNAQGEP 64

Modified RING finger, HC subclass (C4C4-type), found in HOIL-1-interacting protein (HOIP) and similar proteins; HOIP, also known as RING finger protein 31 (RNF31) or zinc in-between-RING-finger ubiquitin-associated domain protein, together with HOIL-1 and SHARPIN, forms the E3-ligase complex (also known as linear-ubiquitin-chain assembly complex LUBAC) that regulates NF-kappaB activity and apoptosis. It also interacts with the atypical mammalian orphan receptor DAX-1, trigger DAX-1 ubiquitination and stabilization, and participate in repressing steroidogenic gene expression. HOIP contains three Npl4 zinc fingers, a central ubiquitin-associated (UBA) domain responsible for the interaction with the N-terminal ubiquitin-like domain (UBL) of HOIL-1L, an RBR domain, and a C-terminal linear chain determining domain (LDD). 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 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 C4C4-type RING finger motif whose overall folding is similar to that of the C3HC4-type RING-HC finger. It is required for RBR-mediated ubiquitination.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|....
gi 40254409  691 QECAVCGWALPRNRMQALISCECTICPECFRQHFTIALKEKHITDMVCPACGRP 744
Cdd:cd16631    1 QECPICFNSFPRNKMVSLTSCECKICPDCFKQYFTVVIKEKHIRDLVCPACGLP 54

B-box-type 1 zinc finger found in HOIL-1-interacting protein (HOIP) and similar proteins; HOIP, also termed RING finger protein 31 (RNF31), or zinc in-between-RING-finger ubiquitin-associated domain protein, together with HOIL-1 and SHARPIN, forms the E3-ligase complex (also known as linear-ubiquitin-chain assembly complex LUBAC) that regulates NF-kappaB activity and apoptosis. It also interacts with the atypical mammalian orphan receptor DAX-1, trigger DAX-1 ubiquitination and stabilization, and participate in repressing steroidogenic gene expression. HOIP contains a B-box motif that shows high sequence similarity with B-Box-type 1 zinc finger found in tripartite motif-containing proteins (TRIMs). The type 1 B-box (Bbox1) zinc finger is characterized by a C6H2 zinc-binding consensus motif.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|..
gi 40254409  214 CFLCGSAPGTLHCPACNQVSCPACDILFHGHPSRAHHLRQAL 255
Cdd:cd19815    2 CDLCGEAAASVFCASCEDKLCLSCDDLYHKHPARRSHHRQPI 43

PNGase/UBA or UBX (PUB) domain of p97 adaptor proteins; The PUB domain is found in p97 adaptor proteins such as PNGase, UBXD1 (UBX domain-containing protein 1), and RNF31 (RING finger protein 31). It functions as a p97 (also known as valosin-containing protein or VCP) adaptor by interacting with the D1 and/or D2 ATPase domains. The p97, a type II AAA+ ATPase, is involved in a variety of cellular processes such as the deglycosylation of ERAD substrates, membrane fusion, transcription factor activation and cell cycle regulation through differential binding to specific adaptor proteins. The PUB domain in UBX-domain protein 1 (UBXD1), which is widely expressed in higher eukaryotes (except for fungi) and which is involved in substrate recruitment to p97, interacts strongly with the C-terminus of p97. Peptide:N-glycanase (PNGase), a deglycosylating enzyme that functions in proteasome-dependent degradation of misfolded glycoproteins which are translocated from the endoplasmic reticulum (ER) to the cytosol during ERAD, associates with the ubiquitin-proteasome system proteins mediated by the N-terminal PUB domain. PNGase is present in all eukaryotic organisms; however, the yeast PNGase ortholog does not contain the PUB domain. The RNF31 protein, also known as HOIP or Zibra, contains an N-terminal PUB domain similar to those in PNGase and UBXD1, suggesting its association with p97.

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 40254409   66 NYLNTLSTALNILEKYGRNLLS-PQRPRYwRSVKFNNPVFRSTVDAVQGGRDVLRLYGYTEERPDGLSFPEGQEEPDE 142
Cdd:cd09212    8 NDLEAFKEALKTLLKILDNILSnPTEEKY-RRIRLSNKAFQEKVLPVPGGLELLLALGFVEETESGESFLVLPDDADV 84

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

                            10        20        30        40        50        60
                    ....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 40254409     773 ALFHKKLTEAVLMRDPKFLWC--AQCSFGFIYERE--QLEATCPQCHQTFCVRCKRQWeeqHRGRSC 835
Cdd:smart00647    1 EKYERLLLESYVESNPDLKWCpaPDCSAAIIVTEEegCNRVTCPKCGFSFCFRCKVPW---HSPVSC 64

BRcat (benign-catalytic) 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 as 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 BRcat domain adopts the same fold as the Rcat domain while lacking 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. The model corresponds to the BRcat domain.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|....*.
gi 40254409  787 DPKFLWC--AQCSFGFIYE--REQLEATCPQCHQTFCVRCKRQWeeqHRGRSCEDF 838
Cdd:cd20335    1 NPNLRWCptPDCGGVIRVEepGDGPRVTCPSCGTSFCFKCKEEW---HEGLTCEEY 53

BRcat domain found in an uncharacterized subfamily of RBR proteins; This subfamily contains uncharacterized members of the RBR family, including Arabidopsis thaliana mutator-like transposase, hypothetical protein F9K21.90, and hypothetical protein T16H5.30. The RBR family of RING-type E3 ligases are characterized by containing a 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 corrected as 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 BRcat domain adopts the same fold as the Rcat domain while lacking 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.

                         10        20        30
                 ....*....|....*....|....*....|.
gi 40254409  808 EATCPQCHQTFCVRCKRQWeeqHRGRSCEDF 838
Cdd:cd22582   29 PRECPKCRRLFCARCKVPW---HAGLSCAEY 56

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.

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gi 40254409  864 DCPKCKfSYALARGGCMHFHCTQCRHQFCSGC 895
Cdd:cd20360    5 DCPKCH-VCIEKNGGCNHMQCSKCKHEFCWMC 35

BRcat 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 BRcat domain of the RNF144 protein subfamily that adopts the same fold as the Rcat domain while lacking the catalytic cysteine residue and ubiquitination activity.

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gi 40254409  811 CPQCHQTFCVRCKRQWeeqHRGRSCEDFQ 839
Cdd:cd20349   38 CPKCGLTFCSICKAAW---HAGQSCDENM 63

BRcat domain found in RING finger protein 216 (RNF216); RNF216, also called Triad domain-containing protein 3 (Triad3A), ubiquitin-conjugating enzyme 7-interacting protein 1, or zinc finger protein inhibiting NF-kappa-B (ZIN), is an RBR-type E3 ubiquitin-protein ligase that interacts with several components of the Toll-like receptor (TLR) signaling pathway and promotes their proteolytic degradation. It negatively regulates the RIG-I RNA sensing pathway through Lys48-linked, ubiquitin-mediated degradation of the tumor necrosis factor (TNF) receptor-associated factor 3 (TRAF3) adapter following RNA virus infection. It also controls ubiquitination and proteasomal degradation of receptor-interacting protein 1 (RIP1), a serine/threonine protein kinase that is critically involved in TNF receptor-1-induced NF-kappa B activation, following disruption of Hsp90 binding. Moreover, RNF216 is involved in inflammatory diseases by strongly inhibiting autophagy in macrophages. It interacts with and ubiquitinates BECN1, a key regulator in autophagy, thereby contributing to BECN1 degradation. It regulates synaptic strength by ubiquitination of Arc, resulting in its rapid proteasomal degradation. It is also a key negative regulator of sustained 2DL4/KIR2DL4 (killer cell Ig-like receptor with two Ig-like domains and a long cytoplasmic domain 4)-mediated NF-kappaB signaling from internalized 2DL4, which functions by promoting ubiquitylation and degradation of endocytosed receptor from early endosomes. Furthermore, RNF216 interacts with human immunodeficiency virus type 1 (HIV-1) virion infectivity factor (Vif) protein, which is essential for the productive infection of primary human CD4 T lymphocytes and macrophages. Mutations in RNF216 may result in Gordon Holmes syndrome, a condition defined by hypogonadotropic hypogonadism and cerebellar ataxia, as well as in autosomal recessive Huntington-like disorder. RNF216 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 RNF216 that adopts the same fold as the Rcat domain while lacking the catalytic cysteine residue and ubiquitination activity.

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gi 40254409  793 CAQCSFGFIYER-EQLEATC--PQCHQTFCVRCKRQWeeqHRGRSCEDFQN 840
Cdd:cd20339    7 CPFCNYAAILDPtEVKVFRCpnPECRKESCRKCKKEW---HIPLTCEEVEK 54

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.

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gi 40254409  864 DCPKCKfSYALARGGCMHFHCTQCRHQFCSGCYNAF 899
Cdd:cd22585    4 RCPKCK-SLIEKIDGCNHVTCTRCGTHICWVCLKVF 38

RING finger, HC subclass, found in the family of RING finger proteins RNF19A, RNF19B and similar proteins; The family includes RING finger protein RNF19A and RNF19B, both of which are transmembrane (TM) domain-containing RBR-type E3 ubiquitin-protein ligases. RNF19A, also known as double ring-finger protein (Dorfin) or p38, localizes to the ubiquitylated inclusions in Parkinson's disease (PD), dementia with Lewy bodies, multiple system atrophy, and amyotrophic lateral sclerosis (ALS). It interacts with Psmc3, a protein component of the 19S regulatory cap of the 26S proteasome, and further participates in the ubiquitin-proteasome system in acrosome biogenesis, spermatid head shaping, and development of the head-tail coupling apparatus and tail. It modulates the ubiquitination and degradation of calcium-sensing receptor (CaR), which may contribute to a general mechanism for CaR quality control during biosynthesis. Moreover, RNF19A can also ubiquitylate mutant superoxide dismutase 1 (SOD1), the causative gene of familial ALS. It may associate with endoplasmic reticulum-associated degradation (ERAD) pathway, which is related to the pathogenesis of neurodegenerative disorders, such as PD or Alzheimer's disease. RNF19B, also known as IBR domain-containing protein 3 or natural killer lytic-associated molecule (NKLAM), plays a role in controlling tumor dissemination and metastasis. It is involved in the cytolytic function of natural killer (NK) cells and cytotoxic T lymphocytes (CTLs). It interacts with ubiquitin conjugates UbcH7 and UbcH8, and ubiquitinates uridine kinase like-1 (URKL-1) protein, targeting it for degradation. Moreover, RNF19B is a novel component of macrophage phagosomes and plays a role in macrophage anti-bacterial activity. It functions as a novel modulator of macrophage inducible nitric oxide synthase (iNOS) expression. Both RNF19A and RNF19B contain an RBR domain followed by three TMs. 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 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.

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gi 40254409  692 ECAVCGWALPRNRMQALISCECTICPECFRQHFTIALKEKHiTDMVCPAC 741
Cdd:cd16629    2 ECPLCLDDLSPEFFPILLSCEHRSCRDCLRQYLTIEISESR-VNISCPEC 50

Rcat domain found in RING finger protein 217 (RNF217); RNF217, also called IBR domain-containing protein 1 (IBRDC1), is a transmembrane (TM) domain-containing RBR-type E3 ubiquitin-protein ligase, with different splice variants, that is mainly expressed in testis and skeletal muscle. It interacts with the anti-apoptotic protein HAX1, and is adjacent to a translocation breakpoint involving ETV6 in childhood acute lymphoblastic leukemia (ALL). RNF217 contains an RBR domain followed by TMs. 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 RNF217 that is essential for RBR E3 ligase activity and adopts the same fold as the BRcat domain.

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gi 40254409  859 QENGIDCPKCKFsYALARGGCMHFHCTQCRHQFCSGC 895
Cdd:cd20350    2 QRNAQKCPKCKV-YIQRSEGCDHMTCSQCNTNFCYRC 37