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        50
                   ....*....|....*....|....*....|....*....|....*....|....*
gi 398366231   195 CSICLSEEPVAPRMVTCGHIFCLSCLLNFFsieetvknketgyskKKKYKECPLC 249
Cdd:smart00184   1 CPICLEEYLKDPVILPCGHTFCRSCIRKWL---------------ESGNNTCPIC 40

Ring finger domain;

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|....*....
gi 398366231  193 QNCSICLSE--EPVAPRMVTCGHIFCLSCLLNFFSIEETvknketgyskkkkykeCPLC 249
Cdd:pfam13639   1 DECPICLEEfeEGDKVVVLPCGHHFHRECLDKWLRSSNT----------------CPLC 43

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        50
                   ....*....|....*....|....*....|....*....|....*....|....*
gi 398366231   195 CSICLSEEPVAPRMVTCGHIFCLSCLLNFFsieetvknketgyskKKKYKECPLC 249
Cdd:smart00184   1 CPICLEEYLKDPVILPCGHTFCRSCIRKWL---------------ESGNNTCPIC 40

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.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|....*
gi 398366231 195 CSICLsEEPVAPRMVTCGHIFCLSCLLNFFSIEEtvknketgyskkkkyKECPLC 249
Cdd:cd16449    3 CPICL-ERLKDPVLLPCGHVFCRECIRRLLESGS---------------IKCPIC 41

RING finger, HC subclass, found in tripartite motif-containing protein 38 (TRIM38) and similar proteins; TRIM38, also known as RING finger protein 15 (RNF15) or zinc finger protein RoRet, is an E3 ubiquitin-protein ligase that promotes K63- and K48-linked ubiquitination of cellular proteins and also catalyzes self-ubiquitination. It negatively regulates Tumor necrosis factor alpha (TNF-alpha)- and interleukin-1beta-triggered Nuclear factor-kappaB (NF-kappaB) activation by mediating lysosomal-dependent degradation of transforming growth factor beta (TGFbeta)-activated kinase 1 (TAK1)-binding protein (TAB)2/3, two critical components of the TAK1 kinase complex. It also inhibits TLR3/4-mediated activation of NF-kappaB and interferon regulatory factor 3 (IRF3) by mediating ubiquitin-proteasomal degradation of TNF receptor-associated factor 6 (Traf6) and NAK-associated protein 1 (Nap1), respectively. Moreover, TRIM38 negatively regulates TLR3-mediated interferon beta (IFN-beta) signaling by targeting ubiquitin-proteasomal degradation of TIR domain-containing adaptor inducing IFN-beta (TRIF). It functions as a valid target for autoantibodies in primary Sjogren's Syndrome. TRIM38 belongs the C-IV subclass of the TRIM (tripartite motif) family of proteins that are defined by their N-terminal RBCC (RING, Bbox, and coiled coil) domains, including three consecutive zinc-binding domains, a C3HC4-type RING-HC finger, a B-box, and two coiled coil domains, as well as a B30.2/SPRY (SplA and ryanodine receptor) domain positioned C-terminal to the RBCC domain.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|....*..
gi 398366231 195 CSICLS--EEPVAprmVTCGHIFCLSCLLNFFsieETVKNKETGYskkkKYKECPLC 249
Cdd:cd16600    8 CSICLQlmTEPVS---INCGHSYCKRCIVSFL---ENQSQLEPGL----ETFSCPQC 54

RING finger, HC subclass, found in tripartite motif-containing protein TRIM25 and similar proteins; TRIM25, also known as estrogen-responsive finger protein (EFP), RING finger protein 147 (RNF147), or RING-type E3 ubiquitin transferase, is an E3 ubiquitin/ISG15 ligase that is induced by estrogen and is therefore particularly abundant in placenta and uterus. TRIM25 regulates various cellular processes through E3 ubiquitin ligase activity, transferring ubiquitin and ISG15 to target proteins. It mediates K63-linked polyubiquitination of retinoic acid inducible gene I (RIG-I) that is crucial for downstream antiviral interferon signaling. It is also required for melanoma differentiation-associated gene 5 (MDA5) and mitochondrial antiviral signaling (MAVS, also known as IPS-1, VISA, Cardiff) mediated activation of nuclear factor-kappaB (NF-kappaB) and interferon production. Upon UV irradiation, TRIM25 interacts with mono-ubiquitinated PCNA and promotes its ISG15 modification (ISGylation), suggesting a crucial role in termination of error-prone translesion DNA synthesis. TRIM25 also functions as a novel regulator of p53 and Mdm2. It enhances p53 and Mdm2 abundance by inhibiting their ubiquitination and degradation in 26S proteasomes. Meanwhile, it inhibits p53's transcriptional activity and dampens the response to DNA damage, and is essential for medaka development and this dependence is rescued by silencing of p53. Moreover, TRIM25 is involved in the host cellular innate immune response against retroviral infection. It interferes with the late stage of feline leukemia virus (FeLV) replication. Furthermore, TRIM25 acts as an oncogene in gastric cancer. Its blockade by RNA interference inhibits migration and invasion of gastric cancer cells through transforming growth factor-beta (TGF-beta) signaling, suggesting it presents a novel target for the detection and treatment of gastric cancer. In addition, TRIM25 acts as an RNA-specific activator for Lin28a/TuT4-mediated uridylation. TRIM25 belongs to the C-IV subclass of TRIM (tripartite motif) family of proteins that are defined by their N-terminal RBCC (RING, Bbox, and coiled coil) domains, including three consecutive zinc-binding domains, a C3HC4-type RING-HC finger, Bbox1 and Bbox2, and a coiled coil region, as well as a B30.2/SPRY (SplA and ryanodine receptor) domain positioned C-terminal to the RBCC domain.

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 398366231 194 NCSICLS--EEPVaprMVTCGHIFCLSCllnffsIEETVKNKETG-YSkkkkykeCPLCgsiIGPKRVKPVL 262
Cdd:cd16597    7 TCSICLElfKDPV---TLPCGHNFCGVC------IEKTWDSQHGSeYS-------CPQC---RATFPRRPEL 59

RING finger, HC subclass, found in breast cancer type 1 susceptibility protein (BRCA1) and similar proteins; BRCA1, also known as RING finger protein 53 (RNF53), is a RING finger protein encoded by the tumor suppressor gene BRCA1 that regulates all DNA double-strand break (DSB) repair pathways. BRCA1 is frequently mutated in patients with hereditary breast and ovarian cancer (HBOC). Its mutation is also associated with an increased risk of pancreatic, stomach, laryngeal, fallopian tube, and prostate cancer. It plays an important role in the DNA damage response signaling and has been implicated in various cellular processes such as cell cycle regulation, transcriptional regulation, chromatin remodeling, DNA DSBs, and apoptosis. BRCA1 contains an N-terminal C3HC4-type RING-HC finger, and two BRCT (BRCA1 C-terminus domain) repeats at the C-terminus.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|....*..
gi 398366231 195 CSICLS--EEPVAPRmvtCGHIFCLSCLLNFFsieetvknketgySKKKKYKECPLC 249
Cdd:cd16498   19 CPICLEllKEPVSTK---CDHQFCRFCILKLL-------------QKKKKPAPCPLC 59

RING finger, HC subclass, found in RING finger protein 213 (RNF213) and similar proteins; RNF213, also known as ALK lymphoma oligomerization partner on chromosome 17 or Moyamoya steno-occlusive disease-associated AAA+ and RING finger protein (mysterin), is an intracellular soluble protein that functions as an E3 ubiquitin-protein ligase and AAA+ ATPase, which possibly contributes to vascular development through mechanical processes in the cell. It plays a unique role in endothelial cells for proper gene expression in response to inflammatory signals from the environment. Mutations in RNF213 may be associated with Moyamoya disease (MMD), an idiopathic cerebrovascular occlusive disorder prevalent in East Asia. It also acts as a nuclear marker for acanthomorph phylogeny. RNF213 contains two tandem enzymatically active AAA+ ATPase modules and a C3HC4-type RING-HC finger. It can form a huge ring-shaped oligomeric complex.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|....*..
gi 398366231 193 QNCSICLsEEPVAPRMVTCGHIFCLSCLLNFFSIEETvknketgyskkkkykeCPLC 249
Cdd:cd16561    3 QECSICL-EDLNDPVKLPCDHVFCEECIRQWLPGQMS----------------CPLC 42

zinc-RING finger domain;

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|
gi 398366231  194 NCSICLSE--EPVAPRMVTCGHIFCLSCLlnffsieetvknketgySKKKKYKECPLCGS 251
Cdd:pfam14634   1 HCNKCFKElsKTRPFYLTSCGHIFCEECL-----------------TRLLQERQCPICKK 43

RING finger, HC subclass, found in RING finger protein 138 (RNF138) and similar proteins; RNF138, also known as Nemo-like kinase-associated RING finger protein (NARF) or NLK-associated RING finger protein, is an E3 ubiquitin-protein ligase that plays an important role in glioma cell proliferation, apoptosis, and cell cycle. It specifically cooperates with the E2 conjugating enzyme E2-25K (Hip-2/UbcH1), regulates the ubiquitylation and degradation of T cell factor/lymphoid enhancer factor (TCF/LEF), and further suppresses Wnt-beta-catenin signaling. RNF138, together with three closely related proteins: RNF114, RNF125 and RNF166, forms a novel family of ubiquitin ligases with a C3HC4-type RING-HC finger, a C2HC-, and two C2H2-type zinc fingers, as well as a ubiquitin interacting motif (UIM).

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 398366231 195 CSICLS--EEPVapRMVTCGHIFCLSCLLNffsieetvknketgySKKKKYKECPLC-GSIIGPKR 257
Cdd:cd16544    5 CPVCQEvlKDPV--ELPPCRHIFCKACILL---------------ALRSSGARCPLCrGPVGKTER 53

E3 ubiquitin-protein ligase RMA2; Provisional

                         10        20        30        40        50        60        70        80
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 398366231 194 NCSICLsEEPVAPRMVTCGHIFCLSCLLNFFSIEETVKNKETGYSKKKKYKECPLCGSIIGPKRVKPVLyeddfdvTRLN 273
Cdd:PLN03208  20 DCNICL-DQVRDPVVTLCGHLFCWPCIHKWTYASNNSRQRVDQYDHKREPPKCPVCKSDVSEATLVPIY-------GRGQ 91

                 ....*....
gi 398366231 274 QKPEPGATV 282
Cdd:PLN03208  92 KAPQSGSNV 100

RING finger, HC subclass, found in RING finger protein 222 (RNF222) and similar proteins; RNF222 is an uncharacterized C3HC4-type RING-HC finger-containing protein. It may function as an E3 ubiquitin-protein ligase.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|....*
gi 398366231 195 CSICLSEEPVAPRMVTCGHIFCLSCLlnffsieetVKNKETgyskkkKYKECPLC 249
Cdd:cd16564    3 CPVCYEDFDDAPRILSCGHSFCEDCL---------VKQLVS------MTISCPIC 42

RING finger, HC subclass, found in Saccharomyces cerevisiae increased recombination centers protein 20 (IRC20) and similar proteins; IRC20 is an uncharacterized ATP-dependent helicase that is probably involved in a pathway contributing to genomic integrity. IRC20 contains a typical C3HC4-type RING-HC finger.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|....*.
gi 398366231 194 NCSICLSEEPVaPRMVTCGHIFCLSCllnffsIEETVKNKETgyskkkkykeCPLC 249
Cdd:cd23135    5 SCSICFSEIRS-GAILKCGHFFCLSC------IASWLREKST----------CPLC 43

RING finger, HC subclass, found in Equid alphaherpesvirus 1 (Equine herpesvirus 1/EHV-1) regulatory protein and similar proteins; EHV-1 regulatory protein belongs to the Vmw110 (IPC0) protein family. It contains a typical C3HC4-type RING-HC finger and binds zinc stably.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|....*.
gi 398366231 194 NCSICLSEEPVAPRMVTCGHIFCLSCLLNFFSIEETvknketgyskkkkykeCPLC 249
Cdd:cd23130    2 VCPICLDDPEDEAITLPCLHQFCYTCILRWLQTSPT----------------CPLC 41

RING finger, HC subclass, found in tripartite motif-containing protein 68 (TRIM68) and similar proteins; TRIM68, also known as RING finger protein 137 (RNF137) or SSA protein SS-56 (SS-56), is an E3 ubiquitin-protein ligase that negatively regulates Toll-like receptor (TLR)- and RIG-I-like receptor (RLR)-driven type I interferon production by degrading TRK fused gene (TFG), a novel driver of IFN-beta downstream of anti-viral detection systems. It also functions as a cofactor for androgen receptor-mediated transcription by regulating ligand-dependent transcription of androgen receptor in prostate cancer cells. Moreover, TRIM68 is a cellular target of autoantibody responses in Sjogre's syndrome (SS), as well as systemic lupus erythematosus (SLE). It is also an auto-antigen for T cells in SS and SLE. TRIM68 belongs the C-IV subclass of the TRIM (tripartite motif) family of proteins that are defined by their N-terminal RBCC (RING, Bbox, and coiled coil) domains, including three consecutive zinc-binding domains, a C3HC4-type RING-HC finger, a B-box, and two coiled coil domains, as well as a B30.2/SPRY (SplA and ryanodine receptor) domain positioned C-terminal to the RBCC domain.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|....*...
gi 398366231 194 NCSICLS--EEPVAprmVTCGHIFCLSCLLNFFSIEETVKNkeTGYSkkkkykeCPLC 249
Cdd:cd16610    3 ACPICMTflREPVS---IDCGHSFCHSCLSGLWEVPGESQN--WGYT-------CPLC 48

RING finger, HC subclass, found in RING finger and transmembrane domain-containing protein 1 (RNFT1); RNFT1, also known as protein PTD016, is a multi-pass membrane protein containing a C3HC4-type RING-HC finger. Its biological role remains unclear.

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|.
gi 398366231 195 CSICLSE--EPVaprMVTCGHIFCLSCLLNFFsieetvkNKEtgyskkkkyKECPLCGSII 253
Cdd:cd16741   17 CAICQAEfrKPI---LLICQHVFCEECISLWF-------NRE---------KTCPLCRTVI 58

RING finger, HC subclass, found in RING finger protein 216 (RNF216) and similar proteins; RNF216, also known as Triad domain-containing protein 3 (Triad3A), ubiquitin-conjugating enzyme 7-interacting protein 1, or zinc finger protein inhibiting NF-kappa-B (ZIN), is a RBR-type E3 ubiquitin-protein ligase that interacts with several components of Toll-like receptor (TLR) signaling 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 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 tumor necrosis factor receptor-1 (TNF-R1)-induced NF-kappa B activation, following disruption of Hsp90 binding. Moreover, RNF216 is involved in inflammatory diseases through 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 Killer cell Ig-like receptor (KIR) with two Ig-like domains and a long cytoplasmic domain 4 (2DL4)-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 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. This family corresponds to the RING domain, a C3HC4-type RING-HC finger motif required for RBR-mediated ubiquitination.

                         10        20        30
                 ....*....|....*....|....*....|....*...
gi 398366231 195 CSICLSEEPVApRMVTC--GHIFCLSCLLNffSIEETV 230
Cdd:cd16630    3 CGCCFGDYPFE-EMVQCpeGHLFCKECVRR--YAEEAV 37

RING finger, HC subclass, found in tripartite motif-containing protein 69 (TRIM69) and similar proteins; TRIM69, also known as RFP-like domain-containing protein trimless or RING finger protein 36 (RNF36), is a testis E3 ubiquitin-protein ligase that plays a specific role in apoptosis and may also play an important role in germ cell homeostasis during spermatogenesis. TRIM69 belongs to the C-IV subclass of the TRIM (tripartite motif) family of proteins that are defined by their N-terminal RBCC (RING, Bbox, and coiled coil) domains, including three consecutive zinc-binding domains, a C3HC4-type RING-HC finger, Bbox1 and Bbox2, and a coiled coil region, as well as a B30.2/SPRY (SplA and ryanodine receptor) domain positioned C-terminal to the RBCC domain.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|....*...
gi 398366231 194 NCSICLS--EEPVaprMVTCGHIFCLSCLLNFFsieetvknketgySKKKKYKECPLC 249
Cdd:cd16611    6 HCPLCLDffRDPV---MLSCGHNFCQSCITGFW-------------ELQAEDTTCPEC 47

RING finger, HC subclass, found in RING finger and transmembrane domain-containing protein 2(RNFT2); RNFT2, also known as transmembrane protein 118 (TMEM118), is a multi-pass membrane protein containing a C3HC4-type RING-HC finger. Its biological role remains unclear.

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|....
gi 398366231 192 GQNCSICLSE--EPVaprMVTCGHIFCLSCLLNFFSIEETvknketgyskkkkykeCPLCGSII 253
Cdd:cd16742   13 GDICAICQAEfrEPL---ILICQHVFCEECLCLWFDRERT----------------CPLCRSVV 57

RING finger, H2 subclass, found in synoviolin and similar proteins; Synoviolin, also known as synovial apoptosis inhibitor 1 (Syvn1), Hrd1, or Der3, is an endoplasmic reticulum (ER)-anchoring E3 ubiquitin ligase that functions as a suppressor of ER stress-induced apoptosis and plays a role in homeostasis maintenance. It also targets tumor suppressor gene p53 for proteasomal degradation, suggesting crosstalk between ER associated degradation (ERAD) and p53 mediated apoptotic pathway under ER stress. Moreover, synoviolin controls body weight and mitochondrial biogenesis through negative regulation of the thermogenic coactivator peroxisome proliferator-activated receptor coactivator (PGC)-1beta. It upregulates amyloid beta production by targeting a negative regulator of gamma-secretase, Retention in endoplasmic reticulum 1 (Rer1), for degradation. It is also involved in the degradation of endogenous immature nicastrin, and affects amyloid beta-protein generation. Moreover, synoviolin is highly expressed in rheumatoid synovial cells and may be involved in the pathogenesis of rheumatoid arthritis (RA). It functions as an anti-apoptotic factor that is responsible for the outgrowth of synovial cells during the development of RA. It promotes inositol-requiring enzyme 1 (IRE1) ubiquitination and degradation in synovial fibroblasts with collagen-induced arthritis. Furthermore, the upregulation of synoviolin may represent a protective response against neurodegeneration in Parkinson's disease (PD). In addition, synoviolin is involved in liver fibrogenesis. Synoviolin contains a C3H2C2-type RING-H2 finger.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|....*
gi 398366231 195 CSICLSEEPVAPRMVTCGHIFCLSCLLNFFSIEETvknketgyskkkkykeCPLC 249
Cdd:cd16479    4 CIICREEMTVGAKKLPCGHIFHLSCLRSWLQRQQT----------------CPTC 42

RING finger, HC subclass, found in bifunctional apoptosis regulator (BAR); BAR, also known as RING finger protein 47, was originally identified as an inhibitor of Bax-induced apoptosis. It participates in the block of apoptosis induced by TNF-family death receptors (extrinsic pathway) and mitochondria-dependent apoptosis (intrinsic pathway). BAR is predominantly expressed by neurons in the central nervous system and is involved in the regulation of neuronal survival. It is an endoplasmic reticulum (ER)-associated RING-type E3 ubiquitin ligase that interacts with BI-1 protein and post-translationally regulates its stability, as well as functioning in ER stress. BAR contains an N-terminal C3HC4-type RING-HC finger, a SAM domain, a coiled-coil domain, and a C-terminal transmembrane (TM) domain. This model corresponds to the RING-HC finger responsible for the binding of ubiquitin conjugating enzymes (E2s).

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|....*.
gi 398366231 194 NCSICLsEEPVAPRMVTCGHIFCLSCLLNFFsieetvknketgysKKKKYKECPLC 249
Cdd:cd16497    3 LCHCCY-DLLVNPTTLNCGHSFCRHCLALWW--------------KSSKKTECPEC 43

RING finger, HC subclass, found in Saccharomyces cerevisiae POB3/SPT16 histone-associated protein 1 (ScPSH1) and similar proteins; ScPSH1 is a Cse4-specific E3 ubiquitin ligase that interacts with the kinetochore protein Pat1 and targets the degradation of budding yeast centromeric histone H3 variant, CENP-ACse4, which is essential for faithful chromosome segregation. ScPSH1 contains a C3HC4-type RING-HC finger and a DNA directed RNA polymerase domain.

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|....
gi 398366231 193 QNCSIC---LSEepvaPRMVTCGHIFCLSCLLNFFsieetvknketgysKKKKYKECPLCGSII 253
Cdd:cd16568    5 QECIICheyLYE----PMVTTCGHTYCYTCLNTWF--------------KSNRSLSCPDCRTKI 50

RING finger, HC subclass, found in Candida albicans transcriptional regulator of yeast form adherence 3 (TRY3) and similar proteins; TRY3 acts as a transcription factor required for yeast cell adherence to silicone substrate. It contains a typical C3HC4-type RING-HC finger.

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....
gi 398366231 195 CSICLSeepVA--PRMVTCGHIFCLSCLlnffsieetVKnketgySKKKKYKECPLCgsiigpkRVKPVLYEDD 266
Cdd:cd23137    5 CPICMN---VAwkPVRLECSHVFCLRCL---------VK------AQKQKKDNCPLC-------RAKGAVKAAT 53

RING finger, HC subclass, found in E3 ubiquitin-protein ligase Deltex3 (DTX3), Deltex-3-like (DTX3L) and similar proteins; This subfamily contains Deltex3 (DTX3) and Deltex-3-like (DTX3L), both of which are E3 ubiquitin-protein ligases belonging to the Deltex (DTX) family. DTX3, also known as RING finger protein 154 (RNF154), has a biological function that remains unclear. DTX3L, also known as B-lymphoma- and BAL-associated protein (BBAP) or Rhysin-2 (Rhysin2), regulates endosomal sorting of the G protein-coupled receptor CXCR4 from endosomes to lysosomes. It also regulates subcellular localization of its partner protein, B aggressive lymphoma (BAL), by a dynamic nucleocytoplasmic trafficking mechanism. In contrast to other DTXs, both DTX3 and DTX3L contain a C3HC4-type RING-HC finger, and a previously unidentified C-terminal domain. DTX3L can associate with DTX1 through its unique N termini and further enhance self-ubiquitination.

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|
gi 398366231 194 NCSICLsEEPVAPRMV-TCGHIFCLSCllnffsIEETVKNKetgyskkkkyKECPLCGSI 252
Cdd:cd16506    2 TCPICL-DEIQNKKTLeKCKHSFCEDC------IDRALQVK----------PVCPVCGVV 44

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        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|...
gi 398366231 195 CSICLSEEPV--APRMVTCGHIFCLSCLLNFFSIEetVKNKETGYSkkkkykeCPLCGSIIGP 255
Cdd:cd16629    3 CPLCLDDLSPefFPILLSCEHRSCRDCLRQYLTIE--ISESRVNIS-------CPECSERFHP 56

RING finger, HC subclass, found in yeast Bre1 and its homologs from eukaryotes; Bre1 is an E3 ubiquitin-protein ligase that catalyzes monoubiquitination of histone H2B in concert with the E2 ubiquitin-conjugating enzyme, Rad6. The Rad6-Bre1-mediated histone H2B ubiquitylation modulates the formation of double-strand breaks (DSBs) during meiosis in yeast. it is also required, indirectly, for the methylation of histone 3 on lysine 4 (H3K4) and 79. RNF20, also known as BRE1A and RNF40, also known as BRE1B, are the mammalian homologs of Bre1. They work together to form a heterodimeric Bre1 complex that facilitate the K120 monoubiquitination of histone H2B (H2Bub1), a DNA damage-induced histone modification that is crucial for recruitment of the chromatin remodeler SNF2h to DNA double-strand break (DSB) damage sites. Moreover, the Bre1 complex acts as a tumor suppressor, augmenting expression of select tumor suppressor genes and suppressing select oncogenes. Deficiency in the mammalian histone H2B ubiquitin ligase Bre1 leads to replication stress and chromosomal instability. All subfamily members contain a C3HC4-type RING-HC finger at its C-terminus.

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 398366231 194 NCSIClSEEPVAPRMVTCGHIFCLSCllnffsIEETVKNKetgySKKkkykeCPLCGSIIGPKRVKPV 261
Cdd:cd16499    8 KCSVC-NDRFKDVIITKCGHVFCNEC------VQKRLETR----QRK-----CPGCGKAFGANDVQRI 59

RING finger, HC subclass, found in tripartite motif-containing protein TRIM17 and similar proteins; TRIM17, also known as RING finger protein 16 (RNF16) or testis RING finger protein (Terf), is a crucial E3 ubiquitin ligase that is necessary and sufficient for neuronal apoptosis and contributes to Mcl-1 ubiquitination in cerebellar granule neurons (CGNs). It interacts in a SUMO-dependent manner with nuclear factor of activated T cell NFATc3 transcription factor, and thus inhibits the activity of NFATc3 by preventing its nuclear localization. In contrast, it binds to and inhibits NFATc4 transcription factor in a SUMO-independent manner. Moreover, TRIM17 stimulates degradation of kinetochore protein ZW10 interacting protein (ZWINT), a known component of the kinetochore complex required for the mitotic spindle checkpoint, and negatively regulates cell proliferation. TRIM17 belongs to the C-IV subclass of the TRIM (tripartite motif) family of proteins that are defined by their N-terminal RBCC (RING, Bbox, and coiled coil) domains, including three consecutive zinc-binding domains, a C3HC4-type RING-HC finger, Bbox1 and Bbox2, and a coiled coil region, as well as a B30.2/SPRY (SplA and ryanodine receptor) domain positioned C-terminal to the RBCC domain.

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 398366231 195 CSICLS--EEPVaprMVTCGHIFCLSCLLNFFSIEETVKnketGYSKKKKYKECPLCGSIIGPKRVKP 260
Cdd:cd16595    8 CSICLDyfTDPV---MTTCGHNFCRACIQLSWEKARGKK----GRRKQKGSFPCPECREMSPQRNLRP 68

RING finger, HC subclass, found in peroxin-2 (PEX2) and similar proteins; PEX2, also known as peroxisome biogenesis factor 2, 35 kDa peroxisomal membrane protein, peroxisomal membrane protein 3, peroxisome assembly factor 1 (PAF-1), or RING finger protein 72 (RNF72), is an integral peroxisomal membrane protein with two transmembrane regions and a C3HC4-type RING-HC finger within its cytoplasmically exposed C-terminus. It may be involved in the biogenesis of peroxisomes, as well as in peroxisomal matrix protein import. Mutations in the PEX2 gene are the primary defect in a subset of patients with Zellweger syndrome and related peroxisome biogenesis disorders. Moreover, PEX2 functions as an E3-ubiquitin ligase that mediates the UBC4-dependent polyubiquitination of PEX5, a key player in peroxisomal matrix protein import, to control PEX5 receptor recycling or degradation.

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|.
gi 398366231 193 QNCSICLSEEPVAPRMVTCGHIFCLSCLLNFFSIEETVKnketgyskkkkykeCPLCGSII 253
Cdd:cd16526    2 TECAICGEWPTNNPYSTGCGHVYCYYCIKSNLLADDSFT--------------CPRCGSPV 48

RING finger, HC subclass, found in RING finger protein 39 (RNF39) and similar proteins; RNF39, also called protein HZFw, may play a role in prolonged long term-potentiation (LTP) maintenance. It is involved in the etiology of Behcet's disease (BD). It may also be involved in HIV-1 replication. RNF39 acts as an E3 ubiquitin ligase that inhibits retinoic acid-inducible gene-I (RIG-I)-like receptor (RLR) pathways by mediating K48-linked ubiquitination and proteasomal degradation of DDX3X (DEAD-box RNA helicase 3, X-linked). RNF39 contains a typical C3HC4-type RING-HC finger.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|....*...
gi 398366231 195 CSICLS--EEPVaprMVTCGHIFCLSCLLNFFSIEETVKNKETGYSkkkkykeCPLCG 250
Cdd:cd16592    7 CPICLGyfKDPV---ILDCEHSFCRACIARHWGQEAMEGNGAEGVF-------CPQCG 54

Modified RING finger, C3HGC3-type, found in RING finger and WD repeat domain-containing protein 3 (RFWD3) and similar proteins; RFWD3, also known as RING finger protein 201 (RNF201) or FLJ10520, is an E3 ubiquitin-protein ligase that forms a complex with Mdm2 and p53 to synergistically ubiquitinate p53 and acts as a positive regulator of p53 stability in response to DNA damage. It is phosphorylated by checkpoint kinase ATM/ATR and the phosphorylation mutant fails to stimulate p53 ubiquitination. RFWD3 also functions as a novel replication protein A (RPA)-associated protein involved in DNA replication checkpoint control. RFWD3 contains an N-terminal SQ-rich region followed by a RING finger domain that exhibits robust E3 ubiquitin ligase activity toward p53, a coiled-coil domain and three WD40 repeats in the C-terminus, the latter two of which may be responsible for protein-protein interaction. The RING finger in this family is a modified C3HGC3-type RING finger, but not a canonical C3H2C3-type RING-H2 finger or C3HC4-type RING-HC finger.

                         10        20        30        40        50        60        70
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 398366231 191 KGQNCSICLseEPVAP----RMVT--CGHIFCLSCllnffsIEETVKNKEtgyskkkkyKECPLCGSIIGPKRVKPV 261
Cdd:cd16450    1 EGNTCPICF--EPWTSsgehRLVSlkCGHLFGYSC------IEKWLKGKG---------KKCPQCNKKAKRSDIRPL 60

RING finger, HC subclass, found in Arabidopsis thaliana protein CHROMATIN REMODELING 27 (CHR27) and similar proteins; CHR27, also called protein SNF2-RING-HELICASE-LIKE 1, is a probable helicase-like transcription factor involved in transcriptional gene silencing. It associates with SUVR2 and contributes to transcriptional gene silencing at RNA-directed DNA methylation (RdDM) target loci but also at RdDM-independent target loci. It may be involved in nucleosome positioning to form ordered nucleosome arrays on chromatin. It associates with SUVR2 and functions redundantly with FRG2. It is required for the efficient methylation of a broad range of RdDM target loci. CHR27 contains a typical C3HC4-type RING-HC finger.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|....*
gi 398366231 195 CSIClSEEPVAPRMVTCGHIFCLSCLLNFFsieetvknkeTGYSKKKKYKECPLC 249
Cdd:cd23142    3 CPIC-NDPPEDAVVTLCGHVFCCECVFQYL----------SSDRTCRQFNHCPLC 46

RING finger, HC subclass, found in Arabidopsis thaliana RING membrane-anchor proteins (AtRMAs) and similar proteins; AtRMAs, including AtRma1, AtRma2, and AtRma3, are endoplasmic reticulum (ER)-localized Arabidopsis homologs of human outer membrane of the ER-anchor E3 ubiquitin-protein ligase, RING finger protein 5 (RNF5). AtRMAs possess E3 ubiquitin ligase activity, and may play a role in the growth and development of Arabidopsis. The AtRMA1 and AtRMA3 genes are predominantly expressed in major tissues, such as cotyledons, leaves, shoot-root junction, roots, and anthers, while AtRMA2 expression is restricted to the root tips and leaf hydathodes. AtRma1 probably functions with the Ubc4/5 subfamily of E2. AtRma2 is likely involved in the cellular regulation of ABP1 expression levels through interacting with auxin binding protein 1 (ABP1). AtRMA proteins contain an N-terminal C3HC4-type RING-HC finger and a trans-membrane-anchoring domain in their extreme C-terminal region.

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|
gi 398366231 195 CSICLSE--EPVaprmVT-CGHIFCLSCLLNFFsieetvknketgySKKKKYKECPLCGS 251
Cdd:cd16745    3 CNICLDLaqDPV----VTlCGHLFCWPCLHKWL-------------RRQSSQPECPVCKA 45

RING finger, HC subclass, found in RING finger protein 185 (RNF185) and similar proteins; RNF185 is an E3 ubiquitin-protein ligase of endoplasmic reticulum-associated degradation (ERAD) that targets cystic fibrosis transmembrane conductance regulator (CFTR). It controls the degradation of CFTR and CFTR F508del allele in a RING- and proteasome-dependent manner, but does not control that of other classical ERAD model substrates. It also negatively regulates osteogenic differentiation by targeting dishevelled2 (Dvl2), a key mediator of the Wnt signaling pathway, for degradation. Moreover, RNF185 regulates selective mitochondrial autophagy through interaction with the Bcl-2 family protein BNIP1. It also plays an important role in cell adhesion and migration through the modulation of cell migration by ubiquitinating paxillin. RNF185 contains a C3HC4-type RING-HC finger.

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*..
gi 398366231 195 CSICLSEEPVAPrMVTCGHIFCLSCLLNFFsieETVKNKETgyskkkkykeCPLCGSIIGPKRVKPV 261
Cdd:cd16744    3 CNICLDTAKDAV-VSLCGHLFCWPCLHQWL---ETRPNRQV----------CPVCKAGISRDKVIPL 55

RING finger, HC subclass, found in tripartite motif-containing protein 77 (TRIM77) and similar proteins; TRIM77 belongs to the C-IV subclass of the TRIM (tripartite motif) family of proteins that are defined by their N-terminal RBCC (RING, Bbox, and coiled coil) domains, including two consecutive zinc-binding domains, a C3HC4-type RING-HC finger and Bbox2, as well as a SPRY/B30.2 domain positioned C-terminal to the RBCC domain.

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|....
gi 398366231 195 CSICLS--EEPVAprmVTCGHIFCLSCLLNFFSieetvkNKETGYSkkkkykeCPLCGSIIGPK 256
Cdd:cd16543    6 CSICLDllKDPVT---IPCGHSFCMNCITLLWD------RKQGVPS-------CPQCRESFPPR 53

RING finger, HC subclass, found in two RING fingers and DRIL [double RING finger linked] 1 (TRIAD1); TRIAD1, also known as 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 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
                 ....*....|....*....|....*....|....
gi 398366231 195 CSICLSEEP--VAPRMvTCGHIFCLSCLLNFFSI 226
Cdd:cd16773    3 CGVCCEDVPkdELFSL-ACGHYFCNDCWKQYLTV 35

RING finger, HC subclass, found in tripartite motif-containing proteins TRIM5, TRIM6, TRIM22, TRIM34 and similar proteins; TRIM5, TRIM6, TRIM22, and TRIM34, four closely related tripartite motif-containing proteins, belong to the C-IV subclass of the TRIM (tripartite motif) family of proteins that are defined by their N-terminal RBCC (RING, Bbox, and coiled coil) domains, including three consecutive zinc-binding domains, a C3HC4-type RING-HC finger, Bbox1 and Bbox2, and a coiled coil region, as well as a B30.2/SPRY (SplA and ryanodine receptor) domain positioned C-terminal to the RBCC domain. TRIM5, also known as RING finger protein 88 (RNF88), is a capsid-specific restriction factor that prevents infection from non-host-adapted retroviruses in a species-specific manner by binding to and destabilizing the retroviral capsid lattice before reverse transcription is completed. Its retroviral restriction activity correlates with the ability to activate TAK1-dependent innate immune signaling. TRIM5 also acts as a pattern recognition receptor that activates innate immune signaling in response to the retroviral capsid lattice. Moreover, TRIM5 plays a role in regulating autophagy through activation of autophagy regulator BECN1 by causing its dissociation from its inhibitors BCL2 and TAB2. It also plays a role in autophagy by acting as a selective autophagy receptor which recognizes and targets HIV-1 capsid protein p24 for autophagic destruction. TRIM6, also known as RING finger protein 89 (RNF89), is an E3-ubiquitin ligase that cooperates with the E2-ubiquitin conjugase UbE2K to catalyze the synthesis of unanchored K48-linked polyubiquitin chains, and further stimulates the interferon-I kappa B kinase epsilon (IKKepsilon) kinase-mediated antiviral response. It also regulates the transcriptional activity of Myc during the maintenance of embryonic stem (ES) cell pluripotency, and may act as a novel regulator for Myc-mediated transcription in ES cells. TRIM22, also known as 50 kDa-stimulated trans-acting factor (Staf-50) or RING finger protein 94 (RNF94), is an E3 ubiquitin-protein ligase that plays an integral role in the host innate immune response to viruses. It has been shown to inhibit the replication of a number of viruses, including HIV-1, hepatitis B, and influenza A. TRIM22 acts as a suppressor of basal HIV-1 long terminal repeat (LTR)-driven transcription by preventing the transcription factor specificity protein 1 (Sp1) binding to the HIV-1 promoter. It also controls FoxO4 activity and cell survival by directing Toll-like receptor 3 (TLR3)-stimulated cells toward type I interferon (IFN) type I gene induction or apoptosis. Moreover, TRIM22 can activate the noncanonical nuclear factor-kappaB (NF-kappaB) pathway by activating I kappa B kinase alpha (IKKalpha). It also regulates nucleotide binding oligomerization domain containing 2 (NOD2)-dependent activation of interferon-beta signaling and nuclear factor-kappaB. TRIM34, also known as interferon-responsive finger protein 1 or RING finger protein 21 (RNF21), may function as antiviral protein that contribute to the defense against retroviral infections.

                         10        20        30        40        50        60
                 ....*....|....*....|....*....|....*....|....*....|....*....|....*...
gi 398366231 195 CSICLS--EEPVAprmVTCGHIFCLSCLlnffsieeTVKNKETGYSKKKkyKECPLCGSIIGPKRVKP 260
Cdd:cd16591    9 CPICLEllTEPLS---LDCGHSFCQACI--------TANHKESVNQEGE--SSCPVCRTSYQPENLRP 63

RING finger, HC subclass, found in tripartite motif-containing proteins TRIM13, TRIM59 and similar proteins; TRIM13 and TRIM59, two closely related tripartite motif-containing proteins, belong to the C-V subclass of the TRIM (tripartite motif) family of proteins that are defined by an N-terminal RBCC (RING, Bbox, and coiled coil) domain, including three consecutive zinc-binding domains, a C3HC4-type RING-HC finger, Bbox1 and Bbox2, and a coiled coil region, followed by a C-terminal transmembrane domain. TRIM13, also known as B-cell chronic lymphocytic leukemia tumor suppressor Leu5, leukemia-associated protein 5, putative tumor suppressor RFP2, RING finger protein 77 (RNF77), or Ret finger protein 2, is an endoplasmic reticulum (ER) membrane anchored E3 ubiquitin-protein ligase that interacts with proteins localized to the ER, including valosin-containing protein (VCP), a protein indispensable for ER-associated degradation (ERAD). TRIM59, also known as RING finger protein 104 (RNF104) or tumor suppressor TSBF-1, is a putative E3 ubiquitin-protein ligase that functions as a novel multiple cancer biomarker for immunohistochemical detection of early tumorigenesis.

                         10        20        30        40        50
                 ....*....|....*....|....*....|....*....|....*....|....*.
gi 398366231 195 CSICLSE-EPvaPRMVTCGHIFCLSCLLNFFSieetvknkETGYSKKKKYKeCPLC 249
Cdd:cd16581    5 CSICYNIfDD--PKILPCSHTFCKNCLEKLLA--------ASGYYLLASLK-CPTC 49

RING finger, HC subclass, found in RING finger protein 14 (RNF14) and similar proteins; RNF14, also known as androgen receptor-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 muscle. It is a ligand-dependent androgen receptor (AR) co-activator and may 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 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
                 ....*....|....*....|....*....|....
gi 398366231 195 CSICLSEEPVAPRMV--TCGHIFCLSCLLNFFSI 226
Cdd:cd16628    8 CNICFLDKLGSECMYfkDCGHVYCKECLKEYFEV 41