RING finger (Really Interesting New Gene) domain and U-box domain superfamily; 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 different Cys/His patterns while some lack a single Cys or His residue at typical Zn ligand positions (the fourth or eighth zinc ligand is prevalently exchanged for an Asp, which can indeed chelate Zn in a RING finger as well). C4C4-, C3HC3D-, C2H2C4-, and C3HC5-type RING fingers are closely related to RING-HC fingers. In contrast, C4HC3- (RING-CH alias RINGv), C3H3C2-, C3H2C2D-, C3DHC3-, and C4HC2H-type RING fingers are more closely related to RING-H2 fingers. However, not all RING finger-containing proteins display regular RING finger features, and the RING finger family has turned out to be multifarious. The degenerate RING fingers of the Siz/PIAS RING (SP-RING) family proteins and sporulation protein RMD5, are characterized by lacking the second, fifth, and sixth Zn2+ ion-coordinating residues. They bind only one Zn2+ ion. On the other hand, the RING fingers of the human APC11 and RBX1 proteins can bind a third Zn atom since they harbor four additional Zn ligands. U-box is a modified form of the RING finger domain that lacks metal chelating Cys and His residues. It resembles the cross-brace RING structure consisting of three beta-sheets and a single alpha-helix, which would be stabilized by salt bridges instead of chelated metal ions. U-box proteins are widely distributed among eukaryotic organisms and show a higher prevalence in plants than in other organisms. RING finger/U-box-containing proteins are 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 enable efficient transfer of ubiquitin from E2 to the substrates.

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gi 18409246  43 LECPICWESFNIVENVPYVLWCGHTLCQNCvfgLQSAVLRLSSQDIRIPF 92
Cdd:cd16587   1 LECPICLESFDEGQLRPKLLHCGHTICEQC---LEKLLASLSINGVRCPF 47

RING finger, HC subclass, found in tripartite motif-containing protein 32 (TRIM32) and similar proteins; TRIM32, also known as 72 kDa Tat-interacting protein, zinc finger protein HT2A, or BBS11, is an E3 ubiquitin-protein ligase that promotes degradation of several targets, including actin, PIASgamma, Abl interactor 2, dysbindin, X-linked inhibitor of apoptosis (XIAP), p73 transcription factor, thin filaments and Z-bands during fasting. It plays important roles in neuronal differentiation of neural progenitor cells, as well as in controlling cell fate in skeletal muscle progenitor cells. It reduces PI3K-Akt-FoxO signaling in muscle atrophy by promoting plakoglobin-PI3K dissociation. It also functions as a pluripotency-reprogramming roadblock that facilitates cellular transition towards differentiation by modulating the levels of Oct4 and cMyc. Moreover, TRIM32 is an intrinsic influenza A virus (IAV) restriction factor which senses and targets the polymerase basic protein 1 (PB1) for ubiquitination and protein degradation. It also plays a significant role in mediating the biological activity of the HIV-1 Tat protein in vivo, binds specifically to the activation domain of HIV-1 Tat, and can also interact with the HIV-2 and EIAV Tat proteins in vivo. Furthermore, TRIM32 regulates myoblast proliferation by controlling turnover of NDRG2 (N-myc downstream-regulated gene). It negatively regulates tumor suppressor p53 to promote tumorigenesis. It also facilitates degradation of MYCN on spindle poles and induces asymmetric cell division in human neuroblastoma cells. In addition, TRIM32 plays important roles in regulation of hyperactivities and positively regulates the development of anxiety and depression disorders induced by chronic stress. It also plays a role in regeneration by affecting satellite cell cycle progression via modulation of the SUMO ligase PIASy (PIAS4). Defects in TRIM32 leads to limb-girdle muscular dystrophy type 2H (LGMD2H), sarcotubular myopathies (STM) and Bardet-Biedl syndrome. TRIM32 belongs to the C-VII subclass of the TRIM (tripartite motif)-NHL family that is 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 domain, as well as a NHL (named after proteins NCL-1, HT2A and Lin-41 that contain repeats folded into a six-bladed beta propeller) repeat domain positioned C-terminal to the RBCC domain. The NHL domain mediates the interaction with Argonaute proteins and consequently allows TRIM32 to modulate the activity of certain miRNAs.

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gi 18409246  43 LECPICWESFNIVENVPYVLWCGHTLCQNCvfgLQSAVLRLSSQDIRIPF 92
Cdd:cd16587   1 LECPICLESFDEGQLRPKLLHCGHTICEQC---LEKLLASLSINGVRCPF 47

RING finger, HC subclass, found in tripartite motif-containing protein 32 (TRIM32) and similar proteins; TRIM32, also known as 72 kDa Tat-interacting protein, zinc finger protein HT2A, or BBS11, is an E3 ubiquitin-protein ligase that promotes degradation of several targets, including actin, PIASgamma, Abl interactor 2, dysbindin, X-linked inhibitor of apoptosis (XIAP), p73 transcription factor, thin filaments and Z-bands during fasting. It plays important roles in neuronal differentiation of neural progenitor cells, as well as in controlling cell fate in skeletal muscle progenitor cells. It reduces PI3K-Akt-FoxO signaling in muscle atrophy by promoting plakoglobin-PI3K dissociation. It also functions as a pluripotency-reprogramming roadblock that facilitates cellular transition towards differentiation by modulating the levels of Oct4 and cMyc. Moreover, TRIM32 is an intrinsic influenza A virus (IAV) restriction factor which senses and targets the polymerase basic protein 1 (PB1) for ubiquitination and protein degradation. It also plays a significant role in mediating the biological activity of the HIV-1 Tat protein in vivo, binds specifically to the activation domain of HIV-1 Tat, and can also interact with the HIV-2 and EIAV Tat proteins in vivo. Furthermore, TRIM32 regulates myoblast proliferation by controlling turnover of NDRG2 (N-myc downstream-regulated gene). It negatively regulates tumor suppressor p53 to promote tumorigenesis. It also facilitates degradation of MYCN on spindle poles and induces asymmetric cell division in human neuroblastoma cells. In addition, TRIM32 plays important roles in regulation of hyperactivities and positively regulates the development of anxiety and depression disorders induced by chronic stress. It also plays a role in regeneration by affecting satellite cell cycle progression via modulation of the SUMO ligase PIASy (PIAS4). Defects in TRIM32 leads to limb-girdle muscular dystrophy type 2H (LGMD2H), sarcotubular myopathies (STM) and Bardet-Biedl syndrome. TRIM32 belongs to the C-VII subclass of the TRIM (tripartite motif)-NHL family that is 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 domain, as well as a NHL (named after proteins NCL-1, HT2A and Lin-41 that contain repeats folded into a six-bladed beta propeller) repeat domain positioned C-terminal to the RBCC domain. The NHL domain mediates the interaction with Argonaute proteins and consequently allows TRIM32 to modulate the activity of certain miRNAs.

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                ....*....|....*....|....*....|....*....|....*....|
gi 18409246  43 LECPICWESFNIVENVPYVLWCGHTLCQNCvfgLQSAVLRLSSQDIRIPF 92
Cdd:cd16587   1 LECPICLESFDEGQLRPKLLHCGHTICEQC---LEKLLASLSINGVRCPF 47

RING finger, HC subclass, found in RING finger protein RNF183, RNF223, RNF225 and similar proteins; RNF183 is an E3 ubiquitin-protein ligase that is upregulated during intestinal inflammation and is negatively regulated by miR-7. It promotes intestinal inflammation by increasing the ubiquitination and degradation of inhibitor of kappa B, thereby resulting in secondary activation of the Nuclear factor-kappaB (NF-kB) pathway. The interaction between RNF183-mediated ubiquitination and miRNA may be an important novel epigenetic mechanism in the pathogenesis of inflammatory bowel disease (IBD). The biological function of RNF223 and RNF225 remains unclear. Members of this family contain an N-terminal C3HC4-type RING-HC finger.

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gi 18409246  43 LECPICWESFNIVENVPYVLWCGHTLCQNCVFGLqSAVLRLSSQDIripffvSCPWC 99
Cdd:cd16556   1 LECSICFSSYDNTFKTPKLLDCGHTFCLECLARL-SLASPPQAERV------PCPLC 50

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.

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gi 18409246  41 EGLECPICWESFNivenVPYVLWCGHTLCQNCVFGLqsavlrLSSQDIRIPFFVSCPWC 99
Cdd:cd16581   1 EELTCSICYNIFD----DPKILPCSHTFCKNCLEKL------LAASGYYLLASLKCPTC 49

RING finger, HC subclass, found in Arabidopsis thaliana protein KEEP ON GOING (KEG) and similar proteins; KEG, also called RING-type E3 ubiquitin transferase KEG, is a RING E3 ubiquitin-protein ligase that mediates E2-dependent protein ubiquitination. It is essential for Arabidopsis growth and development. It acts as a negative regulator of abscisic acid signaling. It is required for ABSCISIC ACID-INSENSITIVE5 (ABI5) degradation, by mediating its ubiquitination. Together with EDR1, KEG may regulate endocytic trafficking and/or the formation of signaling complexes on trans-Golgi network (TGN)/ early endosome (EE) vesicles during stress responses. KEG is a multidomain protein that includes a C3HC4-type RING-HC finger, a kinase domain, ankyrin repeats, and 12 HERC2-like (for HECT and RCC1-like) repeats.

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gi 18409246  44 ECPICWESFNIVENVPYVLWCGHTLCQNCVFGLQSAVLRLSsqdiripffVSCPWCQ 100
Cdd:cd23140   3 ECSVCSEGYNEDERVPLLLQCGHTFCKDCLSQMFIRCTDLT---------LKCPRCR 50

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

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gi 18409246    45 CPICWESFNIvenvPyVLWCGHTLCQNCvfglqsavlrLSSQDIRIPFFVSCP 97
Cdd:pfam13445   1 CPICLELFTD----P-VLPCGHTFCREC----------LEEMSQKKGGKFKCP 38

Modified RING finger, HC subclass (C3HC3D-type), found in Caenorhabditis elegans putative GTP-binding protein trim-23 homolog (arc-1) and similar proteins; arc-1, also called RING-type E3 ubiquitin transferase arc-1, is an E3 ubiquitin-protein ligase that mediates E2-dependent protein ubiquitination. arc-1 contains a modified C3HC3D-type RING-HC finger.

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gi 18409246  43 LECPICWESF--NIVENVPYVLW-CGHTLCQNCVFGLQSAvlrlSSQDIRIPF 92
Cdd:cd23124   2 LECGICQQEYsaDDPLLIPRILTeCGHTICTNCAGTILGQ----SSGSIFCPF 50

RING finger, HC subclass, found in RING finger protein 208 (RNF208) and similar proteins; RNF208 is an E3 ubiquitin-protein ligase whose activity can be modulated by S-nitrosylation. It contains a C3HC4-type RING-HC finger.

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gi 18409246  43 LECPICWESFNIVENVPYVLWCGHTLCQNCvfgLQSAVLRLSSQDiripfFVSCPWCQ 100
Cdd:cd16559   2 LLCPTCGHSYNFTNKRPRILSCLHSVCEEC---LQILYESCPKYK-----FISCPTCK 51

RING finger, HC subclass, found in RING finger protein 182 (RNF182) and similar proteins; RNF182 is a brain-enriched E3 ubiquitin-protein ligase that stimulates E2-dependent polyubiquitination in vitro. It is upregulated in Alzheimer"s disease (AD) brains and neuronal cells exposed to injurious insults. It interacts with ATP6V0C and promotes its degradation by the ubiquitin-proteosome pathway, suggesting a very specific role in controlling the turnover of an essential component of the neurotransmitter release machinery. RNF182 contains an N-terminal C3HC4-type RING-HC finger, and a C-terminal transmembrane domain.

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gi 18409246  43 LECPICWESFNIVENVPYVLWCGHTLCQNCVFGLqsAVLRLSSQDIripffVSCPWCQ 100
Cdd:cd16555   2 LECKICYNRYDLRQRRPKVLECCHRVCAKCLYKI--VDLGDSSPSV-----LVCPFCR 52

RING finger, HC subclass, found in SH3 domain-containing RING finger protein 2 (SH3RF2) and similar proteins; SH3RF2, also known as heart protein phosphatase 1-binding protein (HEPP1), plenty of SH3s (POSH)-eliminating RING protein (POSHER), protein phosphatase 1 regulatory subunit 39, or RING finger protein 158 (RNF158), is a putative E3 ubiquitin-protein ligase that acts as an anti-apoptotic regulator for the c-Jun N-terminal kinase (JNK) pathway by binding to and promoting the proteasomal degradation of SH3RF1 (or POSH), a scaffold protein that is required for pro-apoptotic JNK activation. It may also play a role in cardiac functions together with protein phosphatase 1. SH3RF2 contains an N-terminal C3HC4-type RING-HC finger responsible for the E3 ligase activity and four Src Homology 3 (SH3) domains, which are protein interaction domains that bind to proline-rich ligands with moderate affinity and selectivity, preferentially to PxxP motifs.

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gi 18409246  43 LECPICWESFNIVENVpyvLWCGHTLCQNCVFGLQSAVLRLSSQDIRIP 91
Cdd:cd16749   1 LECPVCFEKLDVTAKV---LPCQHTFCKPCLQRIFKARKELRCPECRTP 46

Modified RING finger, HC subclass (C3HC3D-type), found in Roquin-1; Roquin-1, also known as RING finger and C3H zinc finger protein 1 (RC3H1), or RING finger protein 198 (RNF198), is a ubiquitously expressed RNA-binding protein essential for degradation of inflammation-related mRNAs and maintenance of immune homeostasis. It is localized in cytoplasmic granules and binds to the 3' untranslated region (3'UTR) of inducible costimulator (Icos) mRNA to post-transcriptionally repress its expression. Roquin-1 interacts with the 3'UTR of tumor necrosis factor receptor superfamily member 4 (TNFRSF4) and tumor-necrosis factor-alpha (TNFalpha), and post-transcriptionally regulates A20 mRNA and modulates the activity of the IKK/NF-kappaB pathway. Moreover, Roquin-1 shares functions with its paralog Roquin-2 in the repression of mRNAs controlling T follicular helper cells and systemic inflammation. Roquin-1 contains an N-terminal modified C3HC3D-type RING-HC finger with a potential E3 ubiquitin-ligase function, a highly conserved ROQ domain required for RNA binding and localization to stress granules, and a CCCH-type zinc finger that is involved in RNA recognition, typically contacting AU-rich elements. In addition, both N- and C-terminal to the ROQ domain are combined to form a HEPN (higher eukaryotes and prokaryotes nucleotide-binding) domain that is highly likely to function as an RNA-binding domain.

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gi 18409246  41 EGLECPICWESFNIVENVPYVLWCGHTLCQNCVFGLQ 77
Cdd:cd16781   5 DFLSCPICTQTFDETIRKPISLGCGHTVCKMCLNKLH 41

zinc-RING finger domain;

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gi 18409246    44 ECPICWESFNiVENVPYVLWCGHTLCQNCV 73
Cdd:pfam14634   1 HCNKCFKELS-KTRPFYLTSCGHIFCEECL 29

RING finger, HC subclass, found in tripartite motif-containing protein TRIM65 and similar proteins; TRIM65 is an E3 ubiquitin-protein ligase that interacts with the innate immune receptor MDA5, enhancing its ability to stimulate interferon-beta signaling. It functions as a potential oncogenic protein that negatively regulates p53 through ubiquitination, providing insight into the development of novel approaches targeting TRIM65 for non-small cell lung carcinoma (NSCLC) treatment, and also overcoming chemotherapy resistance. Moreover, TRIM65 negatively regulates microRNA-driven suppression of mRNA translation by targeting TNRC6 proteins for ubiquitination and degradation. TRIM65 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.

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gi 18409246  40 EEGLECPICWESFNivenVPYVLWCGHTLCQNCV 73
Cdd:cd16609   1 EEELTCSICLGLYQ----DPVTLPCQHSFCRACI 30

RING finger, HC subclass, found in SH3 domain-containing RING finger protein 1 (SH3RF1) and similar proteins; SH3RF1, also known as plenty of SH3s (POSH), RING finger protein 142 (RNF142), or SH3 multiple domains protein 2 (SH3MD2), is a trans-Golgi network-associated pro-apoptotic scaffold protein with E3 ubiquitin-protein ligase activity. It also plays a role in calcium homeostasis through the control of the ubiquitin domain protein Herp. It may also have a role in regulating death receptor mediated and c-Jun N-terminal kinase (JNK) mediated apoptosis, linking Rac1 to downstream components. SH3RF1 also enhances the ubiquitination of ROMK1 potassium channel resulting in its increased endocytosis. Moreover, SH3RF1 assembles an inhibitory complex with the actomyosin regulatory protein Shroom3, which links to the actin-myosin network to regulate neuronal process outgrowth. It also forms a complex with apoptosis-linked gene-2 (ALG-2) and ALG-2-interacting protein (ALIX/AIP1) in a calcium-dependent manner to play a role in the regulation of the JNK pathway. Furthermore, direct interaction of SH3RF1 and another molecular scaffold JNK-interacting protein (JIP) is required for apoptotic activation of JNKs. Interaction of SH3RF1 and E3 ubiquitin-protein isopeptide ligases, Siah proteins, further promotes JNK activation and apoptosis. In addition, SH3RF1 binds to and degrades TAK1, a crucial activator of both the JNK and the Relish signaling pathways. SH3RF1 contains an N-terminal C3HC4-type RING-HC finger responsible for the E3 ligase activity and four Src Homology 3 (SH3) domains, which are protein interaction domains that bind to proline-rich ligands with moderate affinity and selectivity, preferentially to PxxP motifs.

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gi 18409246  43 LECPICWESFNIVENVpyvLWCGHTLCQNCVFGLQSavlrlSSQDIRipffvsCPWCQLL 102
Cdd:cd16748   3 LECPVCLERLDATAKV---LPCQHTFCRRCLLGIVG-----SRSELR------CPECRTL 48

RING finger, HC subclass, found in tripartite motif-containing protein 35 (TRIM35) and similar proteins; TRIM35, also known as hemopoietic lineage switch protein 5 (HLS5), is a putative hepatocellular carcinoma (HCC) suppressor that inhibits phosphorylation of pyruvate kinase isoform M2 (PKM2), which is involved in aerobic glycolysis of cancer cells and further suppresses the Warburg effect and tumorigenicity in HCC. It also negatively regulates Toll-like receptor 7 (TLR7)- and TLR9-mediated type I interferon production by suppressing the stability of interferon regulatory factor 7 (IRF7). Moreover, TRIM35 regulates erythroid differentiation by modulating globin transcription factor 1 (GATA-1) activity. TRIM35 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.

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gi 18409246  40 EEGLECPICWESFniveNVPYVLWCGHTLCQNCV 73
Cdd:cd16599   2 KEELLCPICYEPF----REAVTLRCGHNFCKGCV 31

RING finger, HC subclass, found in tripartite motif-containing proteins TRIM9, TRIM67, and similar proteins; Tripartite motif-containing proteins TRIM9 and TRIM67 belong to the C-I subclass of the TRIM (tripartite motif) family of proteins that are defined by their N-terminal RBCC (RING, Bbox, and coiled coil) domains, consisting of three consecutive zinc-binding domains, a C3HC4-type RING-HC finger, Bbox1 and Bbox2, and a coiled coil region, as well as a COS (carboxyl-terminal subgroup one signature) box, a fibronectin type III (FN3) domain, and a B30.2/SPRY (SplA and ryanodine receptor) domain positioned C-terminal to the RBCC domain. TRIM9 (the human ortholog of rat Spring), also known as RING finger protein 91 (RNF91), is a brain-specific E3 ubiquitin-protein ligase collaborating with an E2 ubiquitin conjugating enzyme UBCH5b. TRIM9 plays an important role in the regulation of neuronal functions and participates in neurodegenerative disorders through its ligase activity. TRIM67, also known as TRIM9-like protein (TNL), is a protein selectively expressed in the cerebellum. It interacts with PRG-1, an important molecule in the control of hippocampal excitability dependent on presynaptic LPA2 receptor signaling, and 80K-H, also known as glucosidase II beta, a protein kinase C substrate.

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gi 18409246  40 EEGLECPICWESFNivenVPYVLWCGHTLCQNCVFGLQ 77
Cdd:cd16576   1 EEELKCPVCGSLFT----EPVILPCSHNLCLGCALNIQ 34