Rcat domain found in heme-oxidized IRP2 ubiquitin ligase 1 (HOIL-1) and similar proteins; HOIL-1 is also called RBCK1, HOIL-1L, RanBP-type and C3HC4-type zinc finger-containing protein 1, HBV-associated factor 4, Hepatitis B virus X-associated protein 4, RING finger protein 54 (RNF54), ubiquitin-conjugating enzyme 7-interacting protein 3, or UbcM4-interacting protein 28 (UIP28). Together with the E3 ubiquitin-protein ligase RNF31 (also known as HOIP) and SHANK-associated RH domain interacting protein (SHARPIN), it forms the E3-ligase complex (also known as linear-ubiquitin-chain assembly complex LUBAC) that regulates NF-kappaB activity and apoptosis through conjugation of linear polyubiquitin chains to NF-kappaB essential modulator (also known as NEMO or IKBKG). HOIL-1 plays a crucial role in TNF-alpha-mediated NF-kappaB activation. It also functions as an ubiquitin-protein ligase E3 that interacts with not only PKCbeta but also PKCzeta. It can recognize heme-oxidized IRP2 (iron regulatory protein2) and is thought to affect the turnover of oxidatively damaged proteins. HOIL-1 contains an N-terminal ubiqutin-like (UBL) domain and an Npl4 zinc-finger (NZF) domain, which regulate the interaction with the LUBAC subunit RNF31 and ubiquitin, respectively. The NZF domain belongs to RanBP2-type zinc finger (zf-RanBP2) domain superfamily. In addition, HOIL-1 has 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 HOIL1 that is essential for RBR E3 ligase activity and adopts the same fold as the BRcat domain.

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 768013243 496 MLQQGEAMRCPQCQIVVQKKDGCDWIRCTVCHTEICWVTKGPRWGPGGPGDTSGGCRCRVNGIPCHPSCQNCH 568
Cdd:cd20358    1 LVKSGEAMHCPQCQVIVQKKDGCDWIRCSMCKTEICWVTKGPRWGPGGPGDTSGGCRCRVNGQKCHPNCQNCH 73

ubiquitin-like (Ubl) domain found in heme-oxidized IRP2 ubiquitin ligase 1 (HOIL-1) and similar proteins; HOIL-1, also termed RBCK1, or HOIL-1L, or RanBP-type and C3HC4-type zinc finger-containing protein 1, HBV-associated factor 4, or Hepatitis B virus X-associated protein 4, or RING finger protein 54 (RNF54), or ubiquitin-conjugating enzyme 7-interacting protein 3, or UbcM4-interacting protein 28 (UIP28), together with E3 ubiquitin-protein ligase RNF31 (also known as HOIP) and SHANK-associated RH domain interacting protein (SHARPIN), forms the E3-ligase complex (also known as linear-ubiquitin-chain assembly complex LUBAC) that regulates NF-kappaB activity and apoptosis through conjugation of linear polyubiquitin chains to NF-kappaB essential modulator (also known as NEMO or IKBKG). HOIL-1 plays a crucial role in TNF-alpha-mediated NF-kappaB activation. It also functions as an ubiquitin-protein ligase E3 that interacts with not only PKCbeta but also PKCzeta. It can recognize heme-oxidized IRP2 (iron regulatory protein2) and is thought to affect the turnover of oxidatively damaged proteins. HOIL-1 contains an N-terminal ubiqutin-like (UBL) domain and an Npl4 zinc-finger (NZF) domain, which regulate the interaction with the LUBAC subunit RNF31 and ubiquitin, respectively. The NZF domain belongs to RanBP2-type zinc finger (zf-RanBP2) domain superfamily. In addition, HOIL-1 has a 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 768013243 115 LWVSVEDAQMHTVTIWLTVRPDMTVASLKDMVFLDYGFPPVLQQWVIGQRLARDQETLHSHGVRQNGDSAYLYLLSA 191
Cdd:cd01799    5 IKVYVEDKSSSSGPITLKVRPHTTIASLKRQIFLEYGFPPSVQRWIIGKRLATDDETLLSYGIKDSGDPAFLYLVSA 81

Zinc finger domain; Zinc finger domain in Ran-binding proteins (RanBPs), and other proteins. In RanBPs, this domain binds RanGDP.

                           10        20
                   ....*....|....*....|.
gi 768013243   255 WQCPGCTFINKPTRPGCEMCC 275
Cdd:smart00547   3 WECPACTFLNFASRSKCFACG 23

Rcat domain found in heme-oxidized IRP2 ubiquitin ligase 1 (HOIL-1) and similar proteins; HOIL-1 is also called RBCK1, HOIL-1L, RanBP-type and C3HC4-type zinc finger-containing protein 1, HBV-associated factor 4, Hepatitis B virus X-associated protein 4, RING finger protein 54 (RNF54), ubiquitin-conjugating enzyme 7-interacting protein 3, or UbcM4-interacting protein 28 (UIP28). Together with the E3 ubiquitin-protein ligase RNF31 (also known as HOIP) and SHANK-associated RH domain interacting protein (SHARPIN), it forms the E3-ligase complex (also known as linear-ubiquitin-chain assembly complex LUBAC) that regulates NF-kappaB activity and apoptosis through conjugation of linear polyubiquitin chains to NF-kappaB essential modulator (also known as NEMO or IKBKG). HOIL-1 plays a crucial role in TNF-alpha-mediated NF-kappaB activation. It also functions as an ubiquitin-protein ligase E3 that interacts with not only PKCbeta but also PKCzeta. It can recognize heme-oxidized IRP2 (iron regulatory protein2) and is thought to affect the turnover of oxidatively damaged proteins. HOIL-1 contains an N-terminal ubiqutin-like (UBL) domain and an Npl4 zinc-finger (NZF) domain, which regulate the interaction with the LUBAC subunit RNF31 and ubiquitin, respectively. The NZF domain belongs to RanBP2-type zinc finger (zf-RanBP2) domain superfamily. In addition, HOIL-1 has 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 HOIL1 that is essential for RBR E3 ligase activity and adopts the same fold as the BRcat domain.

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 768013243 496 MLQQGEAMRCPQCQIVVQKKDGCDWIRCTVCHTEICWVTKGPRWGPGGPGDTSGGCRCRVNGIPCHPSCQNCH 568
Cdd:cd20358    1 LVKSGEAMHCPQCQVIVQKKDGCDWIRCSMCKTEICWVTKGPRWGPGGPGDTSGGCRCRVNGQKCHPNCQNCH 73

ubiquitin-like (Ubl) domain found in heme-oxidized IRP2 ubiquitin ligase 1 (HOIL-1) and similar proteins; HOIL-1, also termed RBCK1, or HOIL-1L, or RanBP-type and C3HC4-type zinc finger-containing protein 1, HBV-associated factor 4, or Hepatitis B virus X-associated protein 4, or RING finger protein 54 (RNF54), or ubiquitin-conjugating enzyme 7-interacting protein 3, or UbcM4-interacting protein 28 (UIP28), together with E3 ubiquitin-protein ligase RNF31 (also known as HOIP) and SHANK-associated RH domain interacting protein (SHARPIN), forms the E3-ligase complex (also known as linear-ubiquitin-chain assembly complex LUBAC) that regulates NF-kappaB activity and apoptosis through conjugation of linear polyubiquitin chains to NF-kappaB essential modulator (also known as NEMO or IKBKG). HOIL-1 plays a crucial role in TNF-alpha-mediated NF-kappaB activation. It also functions as an ubiquitin-protein ligase E3 that interacts with not only PKCbeta but also PKCzeta. It can recognize heme-oxidized IRP2 (iron regulatory protein2) and is thought to affect the turnover of oxidatively damaged proteins. HOIL-1 contains an N-terminal ubiqutin-like (UBL) domain and an Npl4 zinc-finger (NZF) domain, which regulate the interaction with the LUBAC subunit RNF31 and ubiquitin, respectively. The NZF domain belongs to RanBP2-type zinc finger (zf-RanBP2) domain superfamily. In addition, HOIL-1 has a 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 768013243 115 LWVSVEDAQMHTVTIWLTVRPDMTVASLKDMVFLDYGFPPVLQQWVIGQRLARDQETLHSHGVRQNGDSAYLYLLSA 191
Cdd:cd01799    5 IKVYVEDKSSSSGPITLKVRPHTTIASLKRQIFLEYGFPPSVQRWIIGKRLATDDETLLSYGIKDSGDPAFLYLVSA 81

Zinc finger domain; Zinc finger domain in Ran-binding proteins (RanBPs), and other proteins. In RanBPs, this domain binds RanGDP.

                           10        20
                   ....*....|....*....|.
gi 768013243   255 WQCPGCTFINKPTRPGCEMCC 275
Cdd:smart00547   3 WECPACTFLNFASRSKCFACG 23

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
                   ....*....|....*....|....*....|....*....|....*....|....*....|...
gi 768013243   128 TIWLTVRPDMTVASLKDMVFLDYGFPPVlQQWVI--GQRLaRDQETLHSHGVrQNGDSAYLYL 188
Cdd:smart00213  12 TITLEVKPSDTVSELKEKIAELTGIPPE-QQRLIykGKVL-EDDRTLADYGI-QDGSTIHLVL 71

Ring finger; E3 ubiquitin-protein ligase activity is intrinsic to the RING domain of c-Cbl and is likely to be a general function of this domain; Various RING fingers exhibit binding activity towards E2 ubiquitin-conjugating enzymes (Ubc' s)

                           10        20        30        40
                   ....*....|....*....|....*....|....*....|....
gi 768013243   340 CPVCYSVLApgEAVVLRECLHTFCRECLQGTIRNSQeaeVSCPF 383
Cdd:smart00184   1 CPICLEEYL--KDPVILPCGHTFCRSCIRKWLESGN---NTCPI 39

Rcat domain found in heme-oxidized IRP2 ubiquitin ligase 1 (HOIL-1) and similar proteins; HOIL-1 is also called RBCK1, HOIL-1L, RanBP-type and C3HC4-type zinc finger-containing protein 1, HBV-associated factor 4, Hepatitis B virus X-associated protein 4, RING finger protein 54 (RNF54), ubiquitin-conjugating enzyme 7-interacting protein 3, or UbcM4-interacting protein 28 (UIP28). Together with the E3 ubiquitin-protein ligase RNF31 (also known as HOIP) and SHANK-associated RH domain interacting protein (SHARPIN), it forms the E3-ligase complex (also known as linear-ubiquitin-chain assembly complex LUBAC) that regulates NF-kappaB activity and apoptosis through conjugation of linear polyubiquitin chains to NF-kappaB essential modulator (also known as NEMO or IKBKG). HOIL-1 plays a crucial role in TNF-alpha-mediated NF-kappaB activation. It also functions as an ubiquitin-protein ligase E3 that interacts with not only PKCbeta but also PKCzeta. It can recognize heme-oxidized IRP2 (iron regulatory protein2) and is thought to affect the turnover of oxidatively damaged proteins. HOIL-1 contains an N-terminal ubiqutin-like (UBL) domain and an Npl4 zinc-finger (NZF) domain, which regulate the interaction with the LUBAC subunit RNF31 and ubiquitin, respectively. The NZF domain belongs to RanBP2-type zinc finger (zf-RanBP2) domain superfamily. In addition, HOIL-1 has 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 HOIL1 that is essential for RBR E3 ligase activity and adopts the same fold as the BRcat domain.

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|...
gi 768013243 496 MLQQGEAMRCPQCQIVVQKKDGCDWIRCTVCHTEICWVTKGPRWGPGGPGDTSGGCRCRVNGIPCHPSCQNCH 568
Cdd:cd20358    1 LVKSGEAMHCPQCQVIVQKKDGCDWIRCSMCKTEICWVTKGPRWGPGGPGDTSGGCRCRVNGQKCHPNCQNCH 73

ubiquitin-like (Ubl) domain found in heme-oxidized IRP2 ubiquitin ligase 1 (HOIL-1) and similar proteins; HOIL-1, also termed RBCK1, or HOIL-1L, or RanBP-type and C3HC4-type zinc finger-containing protein 1, HBV-associated factor 4, or Hepatitis B virus X-associated protein 4, or RING finger protein 54 (RNF54), or ubiquitin-conjugating enzyme 7-interacting protein 3, or UbcM4-interacting protein 28 (UIP28), together with E3 ubiquitin-protein ligase RNF31 (also known as HOIP) and SHANK-associated RH domain interacting protein (SHARPIN), forms the E3-ligase complex (also known as linear-ubiquitin-chain assembly complex LUBAC) that regulates NF-kappaB activity and apoptosis through conjugation of linear polyubiquitin chains to NF-kappaB essential modulator (also known as NEMO or IKBKG). HOIL-1 plays a crucial role in TNF-alpha-mediated NF-kappaB activation. It also functions as an ubiquitin-protein ligase E3 that interacts with not only PKCbeta but also PKCzeta. It can recognize heme-oxidized IRP2 (iron regulatory protein2) and is thought to affect the turnover of oxidatively damaged proteins. HOIL-1 contains an N-terminal ubiqutin-like (UBL) domain and an Npl4 zinc-finger (NZF) domain, which regulate the interaction with the LUBAC subunit RNF31 and ubiquitin, respectively. The NZF domain belongs to RanBP2-type zinc finger (zf-RanBP2) domain superfamily. In addition, HOIL-1 has a 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 768013243 115 LWVSVEDAQMHTVTIWLTVRPDMTVASLKDMVFLDYGFPPVLQQWVIGQRLARDQETLHSHGVRQNGDSAYLYLLSA 191
Cdd:cd01799    5 IKVYVEDKSSSSGPITLKVRPHTTIASLKRQIFLEYGFPPSVQRWIIGKRLATDDETLLSYGIKDSGDPAFLYLVSA 81

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 768013243 124 MHTVTIWLTVRPDMTVASLKDMVFLDYGFPPVLQQWVIGQRLARDQETLHSHGVrQNGDSAYLY 187
Cdd:cd17039    6 LDGKTYTVEVDPDDTVADLKEKIEEKTGIPVEQQRLIYNGKELKDDKTLSDYGI-KDGSTIHLV 68

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 768013243 504 RCPQCQIVVQKKDGCDWIRCTVCHTEICWV 533
Cdd:cd22585    4 RCPKCKSLIEKIDGCNHVTCTRCGTHICWV 33

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.

                         10        20        30
                 ....*....|....*....|....*....|....
gi 768013243 499 QGEAMRCPQCQIVVQKKDGCDWIRCTVCHTEICW 532
Cdd:cd20350    2 QRNAQKCPKCKVYIQRSEGCDHMTCSQCNTNFCY 35

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
                 ....*....|....*....|....*....|
gi 768013243 504 RCPQCQIVVQKKDGCDWIRCTVCHTEICWV 533
Cdd:cd20354   15 PCPGCGTLIEKIDGCNKMTCTKCRTYFCWL 44

RING finger, HC subclass, found in really interesting new gene proteins RING1, RING2 and similar proteins; RING1, also known as polycomb complex protein RING1, RING finger protein 1 (RNF1), or RING finger protein 1A (RING1A), is a transcriptional repressor that is associated with the Polycomb group (PcG) protein complex involved in stable repression of gene activity. RING2, also known as huntingtin-interacting protein 2-interacting protein 3, HIP2-interacting protein 3, protein DinG, RING finger protein 1B (RING1B), RING finger protein 2 (RNF2), or RING finger protein BAP-1, is an E3 ubiquitin-protein ligase that interacts with both nucleosomal DNA and an acidic patch on histone H4 to achieve the specific monoubiquitination of K119 on histone H2A (H2AK119ub), thereby playing a central role in histone code and gene regulation. Both RING1 and RING2 are core components of polycomb repressive complex 1 (PRC1) that functions as an E3-ubuiquitin ligase transferring the mono-ubuiquitin mark to the C-terminal tail of Histone H2A at K118/K119. PRC1 is also capable of chromatin compaction, a function not requiring histone tails, and this activity appears important in gene silencing. RING2 acts as the main E3 ubiquitin ligase on histone H2A of the PRC1 complex, while RING1 may rather act as a modulator of RNF2/RING2 activity. Members of this family contain a C3HC4-type RING-HC finger.

                         10        20        30
                 ....*....|....*....|....*....|....*
gi 768013243 340 CPVCYSVLApgEAVVLRECLHTFCRECLQGTIRNS 374
Cdd:cd16531    4 CPICLGIIK--NTMTVKECLHRFCAECIEKALRLG 36

Rcat domain found in an uncharacterized subfamily of RBR proteins; This subfamily contains uncharacterized members of the RBR family, including Arabidopsis thaliana mutator-like transposase and hypothetical protein At2g19610/F3P11.21. 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. 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 is essential for RBR E3 ligase activity and adopts the same fold as the BRcat domain.

                         10        20        30
                 ....*....|....*....|....*....|
gi 768013243 504 RCPQCQIVVQKKDGCDWIRCtVCHTEICWV 533
Cdd:cd22584    4 RCPQCGHMVELSEGCNHMTC-RCGYEFCYL 32

Ring finger domain;

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....*
gi 768013243  339 ECPVCYSVLAPGEAVVLRECLHTFCRECLQGTIRNSQeaevSCPF 383
Cdd:pfam13639   2 ECPICLEEFEEGDKVVVLPCGHHFHRECLDKWLRSSN----TCPL 42

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.

                         10        20        30        40
                 ....*....|....*....|....*....|....*....|....*....
gi 768013243 338 AECPVCYSVLAPGEAVVLRECLHTFCRECLQG----TIRNSQeAEVSCP 382
Cdd:cd16629    1 LECPLCLDDLSPEFFPILLSCEHRSCRDCLRQyltiEISESR-VNISCP 48

RING-type zinc-finger; This zinc-finger is a typical RING-type of plant ubiquitin ligases.

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|...
gi 768013243  340 CPVCYSVLAPgeavVLRECLHTFCRECLQGTIRNSQEaEVSCP 382
Cdd:pfam13445   1 CPICLELFTD----PVLPCGHTFCRECLEEMSQKKGG-KFKCP 38

ubiquitin-like (Ubl) domain found in the eukaryotic Ddi1 family; The eukaryotic Ddi1 family, including yeast aspartyl protease DNA-damage inducible 1 (Ddi1) and Ddi1-like proteins from vertebrates and other eukaryotes, has been characterized by containing an N-terminal ubiquitin-like (Ubl) domain and a conserved retroviral aspartyl-protease-like domain (RVP) that is important in cell-cycle control. Yeast Ddi1 and many family members also contain a C-terminal ubiquitin-association (UBA) domain, however, Ddi1-like proteins from all vertebrates lack the UBA domain. Ddi1, also termed v-SNARE-master 1 (Vsm1), is an ubiquitin receptor involved in the cell cycle and late secretory pathway in Saccharomyces cerevisiae. It functions as an UBA-Ubl shuttle protein that is required for the proteasome to enable ubiquitin-dependent degradation of its ligands. For instance, Ddi1 plays an essential role in the final stages of proteasomal degradation of Ho endonuclease and of its cognate FBP, Ufo1. Moreover, Ddi1 and its associated protein Rad23p play a cooperative role as negative regulators in yeast PHO pathway. This family also includes mammalian regulatory solute carrier protein family 1 member 1 (RSC1A1), also termed transporter regulator RS1 (RS1), which mediates transcriptional and post-transcriptional regulation of Na(+)-D-glucose cotransporter SGLT1. Ddi1-like proteins play a significant role in cell cycle control, growth control, and trafficking in yeast and may play a crucial role in embryogenesis in higher eukaryotes.

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                 ....*....|....*....|....*....|....*....|....*....|...
gi 768013243 131 LTVRPDMTVASLKDMVFLDYGFPPVLQQ-WVIGQRLARDQETLHSHGVrQNGD 182
Cdd:cd01796   16 LEVSPDMTLEDLKALCEAETGIPAAEQVlLHNGQPLTDDKKTLEALGL-KDGD 67

HC subclass of RING (RING-HC) finger and its variants; The RING finger is a specialized type of Zn-finger of 40 to 60 residues that binds two atoms of zinc. It is defined by the "cross-brace" motif that chelates zinc atoms by eight amino acid residues, typically Cys or His, arranged in a characteristic spacing. Canonical RING motifs have been categorized into two major subclasses, RING-HC (C3HC4-type) and RING-H2 (C3H2C3-type), according to their Cys/His content. There are also many variants of RING fingers. Some have a different Cys/His pattern. Some lack a single Cys or His residue at typical Zn ligand positions, especially, the fourth or eighth zinc ligand is prevalently exchanged for an Asp, which can chelate Zn in a RING finger as well. This family corresponds to the HC subclass of RING (RING-HC) fingers that are characterized by containing C3HC4-type canonical RING-HC fingers or noncanonical RING-HC finger variants, including C4C4-, C3HC3D-, C2H2C4-, and C3HC5-type modified RING-HC fingers. The canonical RING-HC finger has been defined as C-X2-C-X(9-39)-C-X(1-3)-H-X(2-3)-C-X2-C-X(4-48)-C-X2-C. It binds two Zn ions in a unique "cross-brace" arrangement, which distinguishes it from tandem zinc fingers and other similar motifs. RING-HC fingers can be found in a group of diverse proteins with a variety of cellular functions, including oncogenesis, development, viral replication, signal transduction, the cell cycle, and apoptosis. Many of them are ubiquitin-protein ligases (E3s) that serve as scaffolds for binding to ubiquitin-conjugating enzymes (E2s, also referred to as ubiquitin carrier proteins or UBCs) in close proximity to substrate proteins, which enables efficient transfer of ubiquitin from E2 to the substrates.

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                 ....*....|....*....|....*....|....*....|....*
gi 768013243 339 ECPVCYSVLapgEAVVLRECLHTFCRECLQGTIRNSqeaEVSCPF 383
Cdd:cd16449    2 ECPICLERL---KDPVLLPCGHVFCRECIRRLLESG---SIKCPI 40

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.

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                 ....*....|....*....|....*....
gi 768013243 504 RCPQCQIVVQKKDGCDWIRCTVCHTEICW 532
Cdd:cd20352    7 RCPMCHVPIERDEGCAQMMCKNCKHVFCW 35

Modified RING finger, HC subclass (C3HC3D-type), found in tumor necrosis factor (TNF) receptor-associated factor 6 (TRAF6) and similar proteins; TRAF6, also known as interleukin-1 signal transducer or RING finger protein 85 (RNF85), is a cytoplasmic adapter protein that mediates signals induced by the tumor necrosis factor receptor (TNFR) superfamily and Toll-like receptor (TLR)/interleukin-1 receptor (IL-1R) family. It functions as a mediator involved in the activation of mitogen-activated protein kinase (MAPK), phosphoinositide 3-kinase (PI3K), and interferon regulatory factor pathways, as well as in IL-1R-mediated activation of NF-kappaB. TRAF6 is also an oncogene that plays a vital role in K-RAS-mediated oncogenesis. TRAF6 contains an N-terminal domain with a modified C3HC3D-type RING-HC finger and several zinc fingers, and a C-terminal TRAF domain that comprises a coiled coil domain and a conserved TRAF-C domain.

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                 ....*....|....*....|....*....|....*....|....*....
gi 768013243 339 ECPVCYSVLapgEAVVLRECLHTFCRECLQGTIRnsqEAEVSCPfIDNT 387
Cdd:cd16643    3 ECPICLMAL---REPVQTPCGHRFCKACILKSIR---EAGHKCP-VDNE 44

Ring finger; E3 ubiquitin-protein ligase activity is intrinsic to the RING domain of c-Cbl and is likely to be a general function of this domain; Various RING fingers exhibit binding activity towards E2 ubiquitin-conjugating enzymes (Ubc' s)

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                   ....*....|....*....|....*....|....*....|....
gi 768013243   340 CPVCYSVLApgEAVVLRECLHTFCRECLQGTIRNSQeaeVSCPF 383
Cdd:smart00184   1 CPICLEEYL--KDPVILPCGHTFCRSCIRKWLESGN---NTCPI 39

Zinc finger, C3HC4 type (RING finger);

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                  ....*....|....*....|....*....|....*....|....
gi 768013243  339 ECPVCYSVLApgEAVVLRECLHTFCREClqgtIRNSQEAEVSCP 382
Cdd:pfam13923   1 MCPICMDMLK--DPSTTTPCGHVFCQDC----ILRALRAGNECP 38