flap endonuclease GEN homolog 1 isoform X1 [Physeter catodon]
Protein Classification
List of domain hits
| Name | Accession | Description | Interval | E-value | ||||
| PIN_GEN1 | cd09869 | FEN-like PIN domains of Gap Endonuclease 1, a structure-specific, divalent-metal-ion dependent, ... |
2-196 | 3.90e-115 | ||||
FEN-like PIN domains of Gap Endonuclease 1, a structure-specific, divalent-metal-ion dependent, 5' nuclease and homologs; Gap Endonuclease 1 (GEN1) is a Holliday junction resolvase reported to symmetrically cleave Holliday junctions and allow religation without additional processing. GEN1 is a member of the structure-specific, 5' nuclease family (FEN-like) that catalyzes hydrolysis of DNA duplex-containing nucleic acid structures during DNA replication, repair, and recombination. Canonical members of the FEN-like family possess a PIN domain with a two-helical structure insert (also known as the helical arch, helical clamp or I domain) of variable length (approximately 16 to 800 residues), and at the C-terminus of the PIN domain a H3TH (helix-3-turn-helix) domain, an atypical helix-hairpin-helix-2-like region. Both the H3TH domain (not included in this model) and the helical arch/clamp region are involved in DNA binding. The PIN domain belongs to a large nuclease superfamily. The structural properties of the PIN domain indicate its putative active center, consisting of invariant acidic amino acid residues (putative metal-binding residues), is geometrically similar in the active center of structure-specific 5' nucleases, PIN-domain ribonucleases of eukaryotic rRNA editing proteins, and bacterial toxins of toxin-antitoxin (TA) operons. : Pssm-ID: 350217 [Multi-domain] Cd Length: 227 Bit Score: 351.14 E-value: 3.90e-115
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| H3TH_GEN1 | cd09905 | H3TH domain of Gap Endonuclease 1, a structure-specific, divalent-metal-ion dependent, 5' ... |
195-338 | 3.11e-42 | ||||
H3TH domain of Gap Endonuclease 1, a structure-specific, divalent-metal-ion dependent, 5' nuclease; Gap Endonuclease 1 (GEN1): Holliday junction resolvase reported to symmetrically cleave Holliday junctions and allow religation without additional processing. GEN1 is a member of the structure-specific, 5' nuclease family that catalyzes hydrolysis of DNA duplex-containing nucleic acid structures during DNA replication, repair, and recombination. Members of this subgroup include the H3TH (helix-3-turn-helix) domains of GEN1 and other similar eukaryotic 5' nucleases. These nucleases contain a PIN (PilT N terminus) domain with a helical arch/clamp region/I domain (not included here) and inserted within the PIN domain is an atypical helix-hairpin-helix-2 (HhH2)-like region. This atypical HhH2 region, the H3TH domain, has an extended loop with at least three turns between the first two helices, and only three of the four helices appear to be conserved. Both the H3TH domain and the helical arch/clamp region are involved in DNA binding. Studies suggest that a glycine-rich loop in the H3TH domain contacts the phosphate backbone of the template strand in the downstream DNA duplex. These nucleases have a carboxylate rich active site that is involved in binding essential divalent metal ion cofactors (Mg2+ or Mn2+) required for nuclease activity. The first metal binding site is composed entirely of Asp/Glu residues from the PIN domain, whereas, the second metal binding site is composed generally of two Asp residues from the PIN domain and one Asp residue from the H3TH domain. Together with the helical arch and network of amino acids interacting with metal binding ions, the H3TH region defines a positively charged active-site DNA-binding groove in structure-specific 5' nucleases. : Pssm-ID: 188625 Cd Length: 108 Bit Score: 149.43 E-value: 3.11e-42
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| Chromo_2 | pfam18704 | Chromatin organization modifier domain 2; Chromodomains serve as chromatin-targeting modules, ... |
398-457 | 1.15e-24 | ||||
Chromatin organization modifier domain 2; Chromodomains serve as chromatin-targeting modules, general protein interaction elements as well as dimerization sites. They are found in many chromatin-associated proteins that bind modified histone tails for chromatin targeting. Chromodomains often recognize modified lysines through their aromatic cage thus targeting proteins to chromatin. Family members such as GEN1 carry a chomodomain which directly contacts DNA and its truncation severely hampers GEN1's catalytic activity. The chromodomain allows GEN1 to correctly position itself against DNA molecules, and without the chromodomain, GEN1's ability to cut DNA was severely impaired. The GEN1 chromodomain was found to be distantly related to the CDY chromodomains and chromobox proteins, particularly to the chromo-shadow domains of CBX1, CBX3 and CBX5. Furthermore, it is conserved from yeast (Yen1) to humans with the only exception being the Caenorhabditis elegans GEN1, which has a much smaller protein size of 443 amino acids compared to yeast Yen1 (759 aa) or human GEN1 (908 aa). : Pssm-ID: 465841 Cd Length: 63 Bit Score: 97.72 E-value: 1.15e-24
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| Name | Accession | Description | Interval | E-value | |||||
| PIN_GEN1 | cd09869 | FEN-like PIN domains of Gap Endonuclease 1, a structure-specific, divalent-metal-ion dependent, ... |
2-196 | 3.90e-115 | |||||
FEN-like PIN domains of Gap Endonuclease 1, a structure-specific, divalent-metal-ion dependent, 5' nuclease and homologs; Gap Endonuclease 1 (GEN1) is a Holliday junction resolvase reported to symmetrically cleave Holliday junctions and allow religation without additional processing. GEN1 is a member of the structure-specific, 5' nuclease family (FEN-like) that catalyzes hydrolysis of DNA duplex-containing nucleic acid structures during DNA replication, repair, and recombination. Canonical members of the FEN-like family possess a PIN domain with a two-helical structure insert (also known as the helical arch, helical clamp or I domain) of variable length (approximately 16 to 800 residues), and at the C-terminus of the PIN domain a H3TH (helix-3-turn-helix) domain, an atypical helix-hairpin-helix-2-like region. Both the H3TH domain (not included in this model) and the helical arch/clamp region are involved in DNA binding. The PIN domain belongs to a large nuclease superfamily. The structural properties of the PIN domain indicate its putative active center, consisting of invariant acidic amino acid residues (putative metal-binding residues), is geometrically similar in the active center of structure-specific 5' nucleases, PIN-domain ribonucleases of eukaryotic rRNA editing proteins, and bacterial toxins of toxin-antitoxin (TA) operons. Pssm-ID: 350217 [Multi-domain] Cd Length: 227 Bit Score: 351.14 E-value: 3.90e-115
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| H3TH_GEN1 | cd09905 | H3TH domain of Gap Endonuclease 1, a structure-specific, divalent-metal-ion dependent, 5' ... |
195-338 | 3.11e-42 | |||||
H3TH domain of Gap Endonuclease 1, a structure-specific, divalent-metal-ion dependent, 5' nuclease; Gap Endonuclease 1 (GEN1): Holliday junction resolvase reported to symmetrically cleave Holliday junctions and allow religation without additional processing. GEN1 is a member of the structure-specific, 5' nuclease family that catalyzes hydrolysis of DNA duplex-containing nucleic acid structures during DNA replication, repair, and recombination. Members of this subgroup include the H3TH (helix-3-turn-helix) domains of GEN1 and other similar eukaryotic 5' nucleases. These nucleases contain a PIN (PilT N terminus) domain with a helical arch/clamp region/I domain (not included here) and inserted within the PIN domain is an atypical helix-hairpin-helix-2 (HhH2)-like region. This atypical HhH2 region, the H3TH domain, has an extended loop with at least three turns between the first two helices, and only three of the four helices appear to be conserved. Both the H3TH domain and the helical arch/clamp region are involved in DNA binding. Studies suggest that a glycine-rich loop in the H3TH domain contacts the phosphate backbone of the template strand in the downstream DNA duplex. These nucleases have a carboxylate rich active site that is involved in binding essential divalent metal ion cofactors (Mg2+ or Mn2+) required for nuclease activity. The first metal binding site is composed entirely of Asp/Glu residues from the PIN domain, whereas, the second metal binding site is composed generally of two Asp residues from the PIN domain and one Asp residue from the H3TH domain. Together with the helical arch and network of amino acids interacting with metal binding ions, the H3TH region defines a positively charged active-site DNA-binding groove in structure-specific 5' nucleases. Pssm-ID: 188625 Cd Length: 108 Bit Score: 149.43 E-value: 3.11e-42
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| fen_arch | TIGR03674 | flap structure-specific endonuclease; Endonuclease that cleaves the 5'-overhanging flap ... |
1-227 | 1.49e-35 | |||||
flap structure-specific endonuclease; Endonuclease that cleaves the 5'-overhanging flap structure that is generated by displacement synthesis when DNA polymerase encounters the 5'-end of a downstream Okazaki fragment. Has 5'-endo-/exonuclease and 5'-pseudo-Y-endonuclease activities. Cleaves the junction between single and double-stranded regions of flap DNA Pssm-ID: 274717 [Multi-domain] Cd Length: 338 Bit Score: 138.15 E-value: 1.49e-35
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| XPG_I | pfam00867 | XPG I-region; |
125-208 | 1.55e-34 | |||||
XPG I-region; Pssm-ID: 459970 [Multi-domain] Cd Length: 87 Bit Score: 126.48 E-value: 1.55e-34
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| PRK03980 | PRK03980 | flap endonuclease-1; Provisional |
52-227 | 2.69e-33 | |||||
flap endonuclease-1; Provisional Pssm-ID: 235185 [Multi-domain] Cd Length: 292 Bit Score: 130.33 E-value: 2.69e-33
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| Chromo_2 | pfam18704 | Chromatin organization modifier domain 2; Chromodomains serve as chromatin-targeting modules, ... |
398-457 | 1.15e-24 | |||||
Chromatin organization modifier domain 2; Chromodomains serve as chromatin-targeting modules, general protein interaction elements as well as dimerization sites. They are found in many chromatin-associated proteins that bind modified histone tails for chromatin targeting. Chromodomains often recognize modified lysines through their aromatic cage thus targeting proteins to chromatin. Family members such as GEN1 carry a chomodomain which directly contacts DNA and its truncation severely hampers GEN1's catalytic activity. The chromodomain allows GEN1 to correctly position itself against DNA molecules, and without the chromodomain, GEN1's ability to cut DNA was severely impaired. The GEN1 chromodomain was found to be distantly related to the CDY chromodomains and chromobox proteins, particularly to the chromo-shadow domains of CBX1, CBX3 and CBX5. Furthermore, it is conserved from yeast (Yen1) to humans with the only exception being the Caenorhabditis elegans GEN1, which has a much smaller protein size of 443 amino acids compared to yeast Yen1 (759 aa) or human GEN1 (908 aa). Pssm-ID: 465841 Cd Length: 63 Bit Score: 97.72 E-value: 1.15e-24
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| XPGN | smart00485 | Xeroderma pigmentosum G N-region; domain in nucleases |
1-93 | 1.15e-21 | |||||
Xeroderma pigmentosum G N-region; domain in nucleases Pssm-ID: 214690 [Multi-domain] Cd Length: 99 Bit Score: 90.37 E-value: 1.15e-21
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| Name | Accession | Description | Interval | E-value | |||||
| PIN_GEN1 | cd09869 | FEN-like PIN domains of Gap Endonuclease 1, a structure-specific, divalent-metal-ion dependent, ... |
2-196 | 3.90e-115 | |||||
FEN-like PIN domains of Gap Endonuclease 1, a structure-specific, divalent-metal-ion dependent, 5' nuclease and homologs; Gap Endonuclease 1 (GEN1) is a Holliday junction resolvase reported to symmetrically cleave Holliday junctions and allow religation without additional processing. GEN1 is a member of the structure-specific, 5' nuclease family (FEN-like) that catalyzes hydrolysis of DNA duplex-containing nucleic acid structures during DNA replication, repair, and recombination. Canonical members of the FEN-like family possess a PIN domain with a two-helical structure insert (also known as the helical arch, helical clamp or I domain) of variable length (approximately 16 to 800 residues), and at the C-terminus of the PIN domain a H3TH (helix-3-turn-helix) domain, an atypical helix-hairpin-helix-2-like region. Both the H3TH domain (not included in this model) and the helical arch/clamp region are involved in DNA binding. The PIN domain belongs to a large nuclease superfamily. The structural properties of the PIN domain indicate its putative active center, consisting of invariant acidic amino acid residues (putative metal-binding residues), is geometrically similar in the active center of structure-specific 5' nucleases, PIN-domain ribonucleases of eukaryotic rRNA editing proteins, and bacterial toxins of toxin-antitoxin (TA) operons. Pssm-ID: 350217 [Multi-domain] Cd Length: 227 Bit Score: 351.14 E-value: 3.90e-115
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| PIN_FEN1-like | cd09856 | FEN-like PIN domains of Flap endonuclease-1 (FEN1)-like, structure-specific, ... |
5-191 | 7.29e-86 | |||||
FEN-like PIN domains of Flap endonuclease-1 (FEN1)-like, structure-specific, divalent-metal-ion dependent, 5' nucleases; PIN (PilT N terminus) domain of Flap endonuclease-1 (FEN1)-like nucleases: FEN1, Gap endonuclease 1 (GEN1) and Xeroderma pigmentosum complementation group G (XPG) nuclease. Nucleases in this subfamily are members of the structure-specific, 5' nuclease family (FEN-like) that catalyzes hydrolysis of DNA duplex-containing nucleic acid structures during DNA replication, repair, and recombination. Canonical members of the FEN-like family possess a PIN domain with a two-helical structure insert (also known as the helical arch, helical clamp or I domain) of variable length (approximately 16 to 800 residues), and at the C-terminus of the PIN domain a H3TH (helix-3-turn-helix) domain, an atypical helix-hairpin-helix-2-like region. Both the H3TH domain (not included in this model) and the helical arch/clamp region are involved in DNA binding. The PIN domain belongs to a large nuclease superfamily. The structural properties of the PIN domain indicate its putative active center, consisting of invariant acidic amino acid residues (putative metal-binding residues), is geometrically similar in the active center of structure-specific 5' nucleases, PIN-domain ribonucleases of eukaryotic rRNA editing proteins, and bacterial toxins of toxin-antitoxin (TA) operons. Pssm-ID: 350206 [Multi-domain] Cd Length: 235 Bit Score: 274.42 E-value: 7.29e-86
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| PIN_FEN1_EXO1-like | cd00128 | FEN-like PIN domains of Flap endonuclease-1 (FEN1)-like and exonuclease-1 (EXO1)-like ... |
6-189 | 6.46e-63 | |||||
FEN-like PIN domains of Flap endonuclease-1 (FEN1)-like and exonuclease-1 (EXO1)-like nucleases, structure-specific, divalent-metal-ion dependent, 5' nucleases; PIN (PilT N terminus) domain of Flap endonuclease-1 (FEN1) and exonuclease-1 (EXO1)-like nucleases: FEN1, EXO1, Mkt1, Gap endonuclease 1 (GEN1) and Xeroderma pigmentosum complementation group G (XPG) nuclease. These nucleases are members of the structure-specific, 5' nuclease family (FEN-like) that catalyzes hydrolysis of DNA duplex-containing nucleic acid structures during DNA replication, repair, and recombination. Canonical members of the FEN-like family possess a PIN domain with a two-helical structure insert (also known as the helical arch, helical clamp or I domain) of variable length (approximately 16 to 800 residues), and at the C-terminus of the PIN domain a H3TH (helix-3-turn-helix) domain, an atypical helix-hairpin-helix-2-like region. Both the H3TH domain (not included in this model) and the helical arch/clamp region are involved in DNA binding. The PIN domain belongs to a large nuclease superfamily. The structural properties of the PIN domain indicate its putative active center, consisting of invariant acidic amino acid residues (putative metal-binding residues), is geometrically similar in the active center of structure-specific 5' nucleases, PIN-domain ribonucleases of eukaryotic rRNA editing proteins, and bacterial toxins of toxin-antitoxin (TA) operons. Pssm-ID: 350200 [Multi-domain] Cd Length: 162 Bit Score: 209.54 E-value: 6.46e-63
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| PIN_XPG_RAD2 | cd09868 | FEN-like PIN domains of Xeroderma pigmentosum complementation group G (XPG) nuclease, a ... |
2-191 | 5.57e-47 | |||||
FEN-like PIN domains of Xeroderma pigmentosum complementation group G (XPG) nuclease, a structure-specific, divalent-metal-ion dependent, 5' nuclease and homologs; The Xeroderma pigmentosum complementation group G (XPG) nuclease plays a central role in nucleotide excision repair (NER) in cleaving DNA bubble structures or loops. XPG is a member of the structure-specific, 5' nuclease family (FEN-like) that catalyzes hydrolysis of DNA duplex-containing nucleic acid structures during DNA replication, repair, and recombination. Canonical members of the FEN-like family possess a PIN domain with a two-helical structure insert (also known as the helical arch, helical clamp or I domain) of variable length (approximately 16 to 800 residues), and at the C-terminus of the PIN domain a H3TH (helix-3-turn-helix) domain, an atypical helix-hairpin-helix-2-like region. Both the H3TH domain (not included in this model) and the helical arch/clamp region are involved in DNA binding. The PIN domain belongs to a large nuclease superfamily. The structural properties of the PIN domain indicate its putative active center, consisting of invariant acidic amino acid residues (putative metal-binding residues), is geometrically similar in the active center of structure-specific 5' nucleases, PIN-domain ribonucleases of eukaryotic rRNA editing proteins, and bacterial toxins of toxin-antitoxin (TA) operons. Pssm-ID: 350216 [Multi-domain] Cd Length: 209 Bit Score: 166.92 E-value: 5.57e-47
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| PIN_YEN1 | cd09870 | FEN-like PIN domains of Saccharomyces cerevisiae endonuclease 1 (YEN1), Chaetomium ... |
2-201 | 1.28e-45 | |||||
FEN-like PIN domains of Saccharomyces cerevisiae endonuclease 1 (YEN1), Chaetomium thermophilum junction-resolving enzyme GEN1, and fungal homologs; Fungal Endonuclease 1 (YEN1 and GEN1, GEN1 is known as YEN1 in Saccharomyces cerevisiae) is a four-way (Holliday) junction resolvase. Members of this subgroup belong to the structure-specific, 5' nuclease family (FEN-like) that catalyzes hydrolysis of DNA duplex-containing nucleic acid structures during DNA replication, repair, and recombination. Canonical members of the FEN-like family possess a PIN domain with a two-helical structure insert (also known as the helical arch, helical clamp or I domain) of variable length (approximately 16 to 800 residues), and at the C-terminus of the PIN domain a H3TH (helix-3-turn-helix) domain, an atypical helix-hairpin-helix-2-like region. Both the H3TH domain (not included in this model) and the helical arch/clamp region are involved in DNA binding. The PIN domain belongs to a large nuclease superfamily. The structural properties of the PIN domain indicate its putative active center, consisting of invariant acidic amino acid residues (putative metal-binding residues), is geometrically similar in the active center of structure-specific 5' nucleases, PIN-domain ribonucleases of eukaryotic rRNA editing proteins, and bacterial toxins of toxin-antitoxin (TA) operons. Pssm-ID: 350218 [Multi-domain] Cd Length: 229 Bit Score: 163.60 E-value: 1.28e-45
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| H3TH_GEN1 | cd09905 | H3TH domain of Gap Endonuclease 1, a structure-specific, divalent-metal-ion dependent, 5' ... |
195-338 | 3.11e-42 | |||||
H3TH domain of Gap Endonuclease 1, a structure-specific, divalent-metal-ion dependent, 5' nuclease; Gap Endonuclease 1 (GEN1): Holliday junction resolvase reported to symmetrically cleave Holliday junctions and allow religation without additional processing. GEN1 is a member of the structure-specific, 5' nuclease family that catalyzes hydrolysis of DNA duplex-containing nucleic acid structures during DNA replication, repair, and recombination. Members of this subgroup include the H3TH (helix-3-turn-helix) domains of GEN1 and other similar eukaryotic 5' nucleases. These nucleases contain a PIN (PilT N terminus) domain with a helical arch/clamp region/I domain (not included here) and inserted within the PIN domain is an atypical helix-hairpin-helix-2 (HhH2)-like region. This atypical HhH2 region, the H3TH domain, has an extended loop with at least three turns between the first two helices, and only three of the four helices appear to be conserved. Both the H3TH domain and the helical arch/clamp region are involved in DNA binding. Studies suggest that a glycine-rich loop in the H3TH domain contacts the phosphate backbone of the template strand in the downstream DNA duplex. These nucleases have a carboxylate rich active site that is involved in binding essential divalent metal ion cofactors (Mg2+ or Mn2+) required for nuclease activity. The first metal binding site is composed entirely of Asp/Glu residues from the PIN domain, whereas, the second metal binding site is composed generally of two Asp residues from the PIN domain and one Asp residue from the H3TH domain. Together with the helical arch and network of amino acids interacting with metal binding ions, the H3TH region defines a positively charged active-site DNA-binding groove in structure-specific 5' nucleases. Pssm-ID: 188625 Cd Length: 108 Bit Score: 149.43 E-value: 3.11e-42
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| fen_arch | TIGR03674 | flap structure-specific endonuclease; Endonuclease that cleaves the 5'-overhanging flap ... |
1-227 | 1.49e-35 | |||||
flap structure-specific endonuclease; Endonuclease that cleaves the 5'-overhanging flap structure that is generated by displacement synthesis when DNA polymerase encounters the 5'-end of a downstream Okazaki fragment. Has 5'-endo-/exonuclease and 5'-pseudo-Y-endonuclease activities. Cleaves the junction between single and double-stranded regions of flap DNA Pssm-ID: 274717 [Multi-domain] Cd Length: 338 Bit Score: 138.15 E-value: 1.49e-35
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| XPG_I | pfam00867 | XPG I-region; |
125-208 | 1.55e-34 | |||||
XPG I-region; Pssm-ID: 459970 [Multi-domain] Cd Length: 87 Bit Score: 126.48 E-value: 1.55e-34
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| PRK03980 | PRK03980 | flap endonuclease-1; Provisional |
52-227 | 2.69e-33 | |||||
flap endonuclease-1; Provisional Pssm-ID: 235185 [Multi-domain] Cd Length: 292 Bit Score: 130.33 E-value: 2.69e-33
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| rad2 | TIGR00600 | DNA excision repair protein (rad2); All proteins in this family for which functions are known ... |
114-251 | 2.04e-26 | |||||
DNA excision repair protein (rad2); All proteins in this family for which functions are known are flap endonucleases that generate the 3' incision next to DNA damage as part of nucleotide excision repair. This family is related to many other flap endonuclease families including the fen1 family. This family is based on the phylogenomic analysis of JA Eisen (1999, Ph.D. Thesis, Stanford University). [DNA metabolism, DNA replication, recombination, and repair] Pssm-ID: 273166 [Multi-domain] Cd Length: 1034 Bit Score: 116.92 E-value: 2.04e-26
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| PTZ00217 | PTZ00217 | flap endonuclease-1; Provisional |
1-248 | 2.44e-26 | |||||
flap endonuclease-1; Provisional Pssm-ID: 240317 [Multi-domain] Cd Length: 393 Bit Score: 112.41 E-value: 2.44e-26
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| PIN_FEN1 | cd09867 | FEN-like PIN domains of Flap endonuclease-1, a structure-specific, divalent-metal-ion ... |
5-171 | 8.24e-25 | |||||
FEN-like PIN domains of Flap endonuclease-1, a structure-specific, divalent-metal-ion dependent, 5' nuclease and homologs; Flap endonuclease-1 (FEN1) is involved in multiple DNA metabolic pathways, including DNA replication processes (5' flap DNA endonuclease activity and double stranded DNA 5'-exonuclease activity) and DNA repair processes (long-patch base excision repair) in eukaryotes and archaea. Interaction between FEN1 and PCNA (Proliferating cell nuclear antigen) is an essential prerequisite to FEN1's DNA replication functionality and stimulates FEN1 nuclease activity by 10-50 fold. FEN1 belongs to the FEN1-EXO1-like subfamily of structure-specific, 5' nucleases (FEN-like family). Canonical members of the FEN-like family possess a PIN domain with a two-helical structure insert (also known as the helical arch, helical clamp or I domain) of variable length (approximately 16 to 800 residues), and at the C-terminus of the PIN domain a H3TH (helix-3-turn-helix) domain, an atypical helix-hairpin-helix-2-like region. Both the H3TH domain (not included in this model) and the helical arch/clamp region are involved in DNA binding. The PIN domain belongs to a large nuclease superfamily. The structural properties of the PIN domain indicate its putative active center, consisting of invariant acidic amino acid residues (putative metal-binding residues), is geometrically similar in the active center of structure-specific 5' nucleases, PIN-domain ribonucleases of eukaryotic rRNA editing proteins, and bacterial toxins of toxin-antitoxin (TA) operons. FEN1 has a C-terminal extension containing residues forming the consensus PIP-box - Qxx(M/L/I)xxF(Y/F) which serves to anchor FEN1 to PCNA. Pssm-ID: 350215 [Multi-domain] Cd Length: 251 Bit Score: 104.40 E-value: 8.24e-25
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| Chromo_2 | pfam18704 | Chromatin organization modifier domain 2; Chromodomains serve as chromatin-targeting modules, ... |
398-457 | 1.15e-24 | |||||
Chromatin organization modifier domain 2; Chromodomains serve as chromatin-targeting modules, general protein interaction elements as well as dimerization sites. They are found in many chromatin-associated proteins that bind modified histone tails for chromatin targeting. Chromodomains often recognize modified lysines through their aromatic cage thus targeting proteins to chromatin. Family members such as GEN1 carry a chomodomain which directly contacts DNA and its truncation severely hampers GEN1's catalytic activity. The chromodomain allows GEN1 to correctly position itself against DNA molecules, and without the chromodomain, GEN1's ability to cut DNA was severely impaired. The GEN1 chromodomain was found to be distantly related to the CDY chromodomains and chromobox proteins, particularly to the chromo-shadow domains of CBX1, CBX3 and CBX5. Furthermore, it is conserved from yeast (Yen1) to humans with the only exception being the Caenorhabditis elegans GEN1, which has a much smaller protein size of 443 amino acids compared to yeast Yen1 (759 aa) or human GEN1 (908 aa). Pssm-ID: 465841 Cd Length: 63 Bit Score: 97.72 E-value: 1.15e-24
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| XPGN | smart00485 | Xeroderma pigmentosum G N-region; domain in nucleases |
1-93 | 1.15e-21 | |||||
Xeroderma pigmentosum G N-region; domain in nucleases Pssm-ID: 214690 [Multi-domain] Cd Length: 99 Bit Score: 90.37 E-value: 1.15e-21
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| XPGI | smart00484 | Xeroderma pigmentosum G I-region; domain in nucleases |
124-193 | 5.34e-20 | |||||
Xeroderma pigmentosum G I-region; domain in nucleases Pssm-ID: 214689 [Multi-domain] Cd Length: 73 Bit Score: 84.56 E-value: 5.34e-20
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| PIN_EXO1 | cd09857 | FEN-like PIN domains of Exonuclease-1, a structure-specific, divalent-metal-ion dependent, 5' ... |
1-166 | 3.06e-16 | |||||
FEN-like PIN domains of Exonuclease-1, a structure-specific, divalent-metal-ion dependent, 5' nuclease and homologs; exonuclease-1 (EXO1) is involved in multiple, eukaryotic DNA metabolic pathways, including DNA replication processes (5' flap DNA endonuclease activity and double stranded DNA 5'-exonuclease activity), DNA repair processes (DNA mismatch repair (MMR) and post-replication repair (PRR)), recombination, and telomere integrity. EXO1 functions in the MMS2 error-free branch of the PRR pathway in the maintenance and repair of stalled replication forks. Studies also suggest that EXO1 plays both structural and catalytic roles during MMR-mediated mutation avoidance. These nucleases are members of the structure-specific, 5' nuclease family (FEN-like) that catalyzes hydrolysis of DNA duplex-containing nucleic acid structures during DNA replication, repair, and recombination. Canonical members of the FEN-like family possess a PIN domain with a two-helical structure insert (also known as the helical arch, helical clamp or I domain) of variable length (approximately 16 to 800 residues), and at the C-terminus of the PIN domain a H3TH (helix-3-turn-helix) domain, an atypical helix-hairpin-helix-2-like region. Both the H3TH domain (not included in this model) and the helical arch/clamp region are involved in DNA binding. The PIN domain belongs to a large nuclease superfamily. The structural properties of the PIN domain indicate its putative active center, consisting of invariant acidic amino acid residues (putative metal-binding residues), is geometrically similar in the active center of structure-specific 5' nucleases, PIN-domain ribonucleases of eukaryotic rRNA editing proteins, and bacterial toxins of toxin-antitoxin (TA) operons. EXO1 nucleases also have C-terminal Mlh1- and Msh2-binding domains which allow interaction with MMR and PRR proteins, respectively. Pssm-ID: 350207 [Multi-domain] Cd Length: 202 Bit Score: 78.22 E-value: 3.06e-16
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| rad2 | TIGR00600 | DNA excision repair protein (rad2); All proteins in this family for which functions are known ... |
1-115 | 9.17e-16 | |||||
DNA excision repair protein (rad2); All proteins in this family for which functions are known are flap endonucleases that generate the 3' incision next to DNA damage as part of nucleotide excision repair. This family is related to many other flap endonuclease families including the fen1 family. This family is based on the phylogenomic analysis of JA Eisen (1999, Ph.D. Thesis, Stanford University). [DNA metabolism, DNA replication, recombination, and repair] Pssm-ID: 273166 [Multi-domain] Cd Length: 1034 Bit Score: 82.25 E-value: 9.17e-16
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| XPG_N | pfam00752 | XPG N-terminal domain; |
2-93 | 5.39e-13 | |||||
XPG N-terminal domain; Pssm-ID: 395609 [Multi-domain] Cd Length: 100 Bit Score: 65.85 E-value: 5.39e-13
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| H3TH_XPG-like | cd09900 | H3TH domains of Flap endonuclease-1 (FEN1)-like structure specific 5' nucleases: FEN1 ... |
196-240 | 3.32e-09 | |||||
H3TH domains of Flap endonuclease-1 (FEN1)-like structure specific 5' nucleases: FEN1 (archaeal), GEN1, YEN1, and XPG; The 5' nucleases within this family are capable of both 5'-3' exonucleolytic activity and cleaving bifurcated or branched DNA, in an endonucleolytic, structure-specific manner, and are involved in DNA replication, repair, and recombination. This family includes the H3TH (helix-3-turn-helix) domains of archaeal Flap Endonuclease-1 (FEN1), Gap Endonuclease 1 (GEN1), Yeast Endonuclease 1 (YEN1), Xeroderma pigmentosum complementation group G (XPG) nuclease, and other eukaryotic and archaeal homologs. These nucleases contain a PIN (PilT N terminus) domain with a helical arch/clamp region/I domain (not included here) and inserted within the PIN domain is an atypical helix-hairpin-helix-2 (HhH2)-like region. This atypical HhH2 region, the H3TH domain, has an extended loop with at least three turns between the first two helices, and only three of the four helices appear to be conserved. Both the H3TH domain and the helical arch/clamp region are involved in DNA binding. Studies suggest that a glycine-rich loop in the H3TH domain contacts the phosphate backbone of the template strand in the downstream DNA duplex. With the except of the Mkt1-like proteins, the nucleases within this family have a carboxylate rich active site that is involved in binding essential divalent metal ion cofactors (i. e., Mg2+, Mn2+, Zn2+, or Co2+) required for nuclease activity. The first metal binding site is composed entirely of Asp/Glu residues from the PIN domain, whereas, the second metal binding site is composed generally of two Asp residues from the PIN domain and one Asp residue from the H3TH domain. Together with the helical arch and network of amino acids interacting with metal binding ions, the H3TH region defines a positively charged active-site DNA-binding groove in structure-specific 5' nucleases. Pssm-ID: 188620 [Multi-domain] Cd Length: 52 Bit Score: 53.26 E-value: 3.32e-09
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| H3TH_FEN1-XPG-like | cd09897 | H3TH domains of Flap endonuclease-1 (FEN1)-like structure specific 5' nucleases; The 5' ... |
198-252 | 2.23e-08 | |||||
H3TH domains of Flap endonuclease-1 (FEN1)-like structure specific 5' nucleases; The 5' nucleases within this family are capable of both 5'-3' exonucleolytic activity and cleaving bifurcated or branched DNA, in an endonucleolytic, structure-specific manner, and are involved in DNA replication, repair, and recombination. This family includes the H3TH (helix-3-turn-helix) domains of Flap Endonuclease-1 (FEN1), Exonuclease-1 (EXO1), Mkt1, Gap Endonuclease 1 (GEN1), Xeroderma pigmentosum complementation group G (XPG) nuclease, and other eukaryotic and archaeal homologs. These nucleases contain a PIN (PilT N terminus) domain with a helical arch/clamp region/I domain (not included here) and inserted within the PIN domain is an atypical helix-hairpin-helix-2 (HhH2)-like region. This atypical HhH2 region, the H3TH domain, has an extended loop with at least three turns between the first two helices, and only three of the four helices appear to be conserved. Both the H3TH domain and the helical arch/clamp region are involved in DNA binding. Studies suggest that a glycine-rich loop in the H3TH domain contacts the phosphate backbone of the template strand in the downstream DNA duplex. With the except of the Mkt1-like proteins, the nucleases within this family have a carboxylate rich active site that is involved in binding essential divalent metal ion cofactors (i. e., Mg2+, Mn2+, Zn2+, or Co2+) required for nuclease activity. The first metal binding site is composed entirely of Asp/Glu residues from the PIN domain, whereas, the second metal binding site is composed generally of two Asp residues from the PIN domain and one Asp residue from the H3TH domain. Together with the helical arch and network of amino acids interacting with metal binding ions, the H3TH region defines a positively charged active-site DNA-binding groove in structure-specific 5' nucleases. Pssm-ID: 188617 [Multi-domain] Cd Length: 68 Bit Score: 51.44 E-value: 2.23e-08
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| H3TH_XPG | cd09904 | H3TH domain of Xeroderma pigmentosum complementation group G (XPG) nuclease, a ... |
198-252 | 1.08e-07 | |||||
H3TH domain of Xeroderma pigmentosum complementation group G (XPG) nuclease, a structure-specific, divalent-metal-ion dependent, 5' nuclease; The Xeroderma pigmentosum complementation group G (XPG) nuclease plays a central role in nucleotide excision repair (NER) in cleaving DNA bubble structures or loops. XPG is a member of the structure-specific, 5' nuclease family that catalyzes hydrolysis of DNA duplex-containing nucleic acid structures during DNA replication, repair, and recombination. Members of this subgroup include the H3TH (helix-3-turn-helix) domains of XPG and other similar eukaryotic 5' nucleases. These nucleases contain a PIN (PilT N terminus) domain with a helical arch/clamp region/I domain (not included here) and inserted within the PIN domain is an atypical helix-hairpin-helix-2 (HhH2)-like region. This atypical HhH2 region, the H3TH domain, has an extended loop with at least three turns between the first two helices, and only three of the four helices appear to be conserved. Both the H3TH domain and the helical arch/clamp region are involved in DNA binding. Studies suggest that a glycine-rich loop in the H3TH domain contacts the phosphate backbone of the template strand in the downstream DNA duplex. These nucleases have a carboxylate rich active site that is involved in binding essential divalent metal ion cofactors (Mg2+ or Mn2+) required for nuclease activity. The first metal binding site is composed entirely of Asp/Glu residues from the PIN domain, whereas, the second metal binding site is composed generally of two Asp residues from the PIN domain and one Asp residue from the H3TH domain. Together with the helical arch and network of amino acids interacting with metal binding ions, the H3TH region defines a positively charged active-site DNA-binding groove in structure-specific 5' nucleases. Pssm-ID: 188624 [Multi-domain] Cd Length: 97 Bit Score: 50.71 E-value: 1.08e-07
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| H3TH_FEN1-Arc | cd09903 | H3TH domain of Flap Endonuclease-1, a structure-specific, divalent-metal-ion dependent, 5' ... |
198-227 | 9.70e-07 | |||||
H3TH domain of Flap Endonuclease-1, a structure-specific, divalent-metal-ion dependent, 5' nuclease: Archaeal homologs; Members of this subgroup include the H3TH (helix-3-turn-helix) domains of archaeal Flap endonuclease-1 (FEN1), 5' nucleases. FEN1 is involved in multiple DNA metabolic pathways, including DNA replication processes (5' flap DNA endonuclease activity and double stranded DNA 5'-exonuclease activity) and DNA repair processes (long-patch base excision repair) in eukaryotes and archaea. Interaction between FEN1 and PCNA (Proliferating cell nuclear antigen) is an essential prerequisite to FEN1's DNA replication functionality and stimulates FEN1 nuclease activity by 10-50 fold. These nucleases contain a PIN (PilT N terminus) domain with a helical arch/clamp region/I domain (not included here) and inserted within the PIN domain is an atypical helix-hairpin-helix-2 (HhH2)-like region. This atypical HhH2 region, the H3TH domain, has an extended loop with at least three turns between the first two helices, and only three of the four helices appear to be conserved. Both the H3TH domain and the helical arch/clamp region are involved in DNA binding. Studies suggest that a glycine-rich loop in the H3TH domain contacts the phosphate backbone of the template strand in the downstream DNA duplex. The nucleases within this subfamily have a carboxylate rich active site that is involved in binding essential divalent metal ion cofactors (Mg2+ or Mn2+) required for nuclease activity. The first metal binding site is composed entirely of Asp/Glu residues from the PIN domain, whereas, the second metal binding site is composed generally of two Asp residues from the PIN domain and one Asp residue from the H3TH domain. Together with the helical arch and network of amino acids interacting with metal binding ions, the H3TH region defines a positively charged active-site DNA-binding groove in structure-specific 5' nucleases. Also, FEN1 has a C-terminal extension containing residues forming the consensus PIP-box - Qxx(M/L/I)xxF(Y/F) which serves to anchor FEN1 to PCNA. Pssm-ID: 188623 [Multi-domain] Cd Length: 65 Bit Score: 46.82 E-value: 9.70e-07
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| PIN_FEN-like | cd09853 | FEN-like PIN domains of structure-specific 5' nucleases (or Flap endonuclease-1-like) involved ... |
53-168 | 7.42e-06 | |||||
FEN-like PIN domains of structure-specific 5' nucleases (or Flap endonuclease-1-like) involved in DNA replication, repair, and recombination; Structure-specific 5' nucleases are capable of both 5'-3' exonucleolytic activity and cleaving bifurcated or branched DNA, in an endonucleolytic, structure-specific manner. The family includes the PIN (PilT N terminus) domains of Flap endonuclease-1 (FEN1), exonuclease-1 (EXO1), Mkt1, Gap Endonuclease 1 (GEN1), and Xeroderma pigmentosum complementation group G (XPG) nuclease. Also included are the PIN domains of the 5'-3' exonucleases of DNA polymerase I and single domain protein homologs, as well as, the bacteriophage T4- and T5-5' nucleases, and other homologs. Canonical members of this FEN-like family possess a PIN domain with a two-helical structure insert (also known as the helical arch, helical clamp or I domain) of variable length (approximately 16 to 800 residues), and at the C-terminus of the PIN domain a H3TH (helix-3-turn-helix) domain, an atypical helix-hairpin-helix-2-like region. Both the H3TH domain (not included in this model) and the helical arch/clamp region are involved in DNA binding. The PIN domain belongs to a large nuclease superfamily. The structural properties of the PIN domain indicate its putative active center, consisting of invariant acidic amino acid residues (putative metal-binding residues), is geometrically similar in the active center of structure-specific 5' nucleases, PIN-domain ribonucleases of eukaryotic rRNA editing proteins, and bacterial toxins of toxin-antitoxin (TA) operons. Pssm-ID: 350204 [Multi-domain] Cd Length: 174 Bit Score: 47.09 E-value: 7.42e-06
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| H3TH_FEN1-like | cd09901 | H3TH domains of Flap endonuclease-1 (FEN1)-like structure specific 5' nucleases: FEN1 ... |
201-227 | 5.43e-05 | |||||
H3TH domains of Flap endonuclease-1 (FEN1)-like structure specific 5' nucleases: FEN1 (eukaryotic) and EXO1; The 5' nucleases within this family are capable of both 5'-3' exonucleolytic activity and cleaving bifurcated or branched DNA, in an endonucleolytic, structure-specific manner, and are involved in DNA replication, repair, and recombination. This family includes the H3TH (helix-3-turn-helix) domains of eukaryotic Flap Endonuclease-1 (FEN1), Exonuclease-1 (EXO1), and other eukaryotic homologs. These nucleases contain a PIN (PilT N terminus) domain with a helical arch/clamp region/I domain (not included here) and inserted within the PIN domain is an atypical helix-hairpin-helix-2 (HhH2)-like region. This atypical HhH2 region, the H3TH domain, has an extended loop with at least three turns between the first two helices, and only three of the four helices appear to be conserved. Both the H3TH domain and the helical arch/clamp region are involved in DNA binding. Studies suggest that a glycine-rich loop in the H3TH domain contacts the phosphate backbone of the template strand in the downstream DNA duplex. The nucleases within this family have a carboxylate rich active site that is involved in binding essential divalent metal ion cofactors (i. e., Mg2+, Mn2+, Zn2+, or Co2+) required for nuclease activity. The first metal binding site is composed entirely of Asp/Glu residues from the PIN domain, whereas, the second metal binding site is composed generally of two Asp residues from the PIN domain and one Asp residue from the H3TH domain. Together with the helical arch and network of amino acids interacting with metal binding ions, the H3TH region defines a positively charged active-site DNA-binding groove in structure-specific 5' nucleases. Pssm-ID: 188621 [Multi-domain] Cd Length: 73 Bit Score: 42.14 E-value: 5.43e-05
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| H3TH_StructSpec-5'-nucleases | cd00080 | H3TH domains of structure-specific 5' nucleases (or flap endonuclease-1-like) involved in DNA ... |
201-227 | 8.18e-05 | |||||
H3TH domains of structure-specific 5' nucleases (or flap endonuclease-1-like) involved in DNA replication, repair, and recombination; The 5' nucleases of this superfamily are capable of both 5'-3' exonucleolytic activity and cleaving bifurcated or branched DNA, in an endonucleolytic, structure-specific manner, and are involved in DNA replication, repair, and recombination. The superfamily includes the H3TH (helix-3-turn-helix) domains of Flap Endonuclease-1 (FEN1), Exonuclease-1 (EXO1), Mkt1, Gap Endonuclease 1 (GEN1) and Xeroderma pigmentosum complementation group G (XPG) nuclease. Also included are the H3TH domains of the 5'-3' exonucleases of DNA polymerase I and single domain protein homologs, as well as, the bacteriophage T4 RNase H, T5-5'nuclease, and other homologs. These nucleases contain a PIN (PilT N terminus) domain with a helical arch/clamp region/I domain (not included here) and inserted within the C-terminal region of the PIN domain is an atypical helix-hairpin-helix-2 (HhH2)-like region. This atypical HhH2 region, the H3TH domain, has an extended loop with at least three turns between the first two helices, and only three of the four helices appear to be conserved. Both the H3TH domain and the helical arch/clamp region are involved in DNA binding. Studies suggest that a glycine-rich loop in the H3TH domain contacts the phosphate backbone of the template strand in the downstream DNA duplex. Typically, the nucleases within this superfamily have a carboxylate rich active site that is involved in binding essential divalent metal ion cofactors (i. e., Mg2+, Mn2+, Zn2+, or Co2+) required for nuclease activity. The first metal binding site is composed entirely of Asp/Glu residues from the PIN domain, whereas, the second metal binding site is composed generally of two Asp residues from the PIN domain and one or two Asp residues from the H3TH domain. Together with the helical arch and network of amino acids interacting with metal binding ions, the H3TH region defines a positively charged active-site DNA-binding groove in structure-specific 5' nucleases. Pssm-ID: 188616 [Multi-domain] Cd Length: 71 Bit Score: 41.59 E-value: 8.18e-05
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| H3TH_YEN1 | cd09906 | H3TH domain of Yeast Endonuclease 1, a structure-specific, divalent-metal-ion dependent, 5' ... |
195-243 | 8.38e-05 | |||||
H3TH domain of Yeast Endonuclease 1, a structure-specific, divalent-metal-ion dependent, 5' nuclease; Yeast Endonuclease 1 (YEN1): Holliday junction resolvase which promotes reciprocal exchange during mitotic recombination to maintain genome integrity in budding yeast. YEN1 is a member of the structure-specific, 5' nuclease family that catalyzes hydrolysis of DNA duplex-containing nucleic acid structures during DNA replication, repair, and recombination. Members of this subgroup include the H3TH (helix-3-turn-helix) domains of YEN1 and other similar fungal 5' nucleases. These nucleases contain a PIN (PilT N terminus) domain with a helical arch/clamp region/I domain (not included here) and inserted within the PIN domain is an atypical helix-hairpin-helix-2 (HhH2)-like region. This atypical HhH2 region, the H3TH domain, has an extended loop with at least three turns between the first two helices, and only three of the four helices appear to be conserved. Both the H3TH domain and the helical arch/clamp region are involved in DNA binding. Studies suggest that a glycine-rich loop in the H3TH domain contacts the phosphate backbone of the template strand in the downstream DNA duplex. These nucleases have a carboxylate rich active site that is involved in binding essential divalent metal ion cofactors (Mg2+ or Mn2+) required for nuclease activity. The first metal binding site is composed entirely of Asp/Glu residues from the PIN domain, whereas, the second metal binding site is composed generally of two Asp residues from the PIN domain and one Asp residue from the H3TH domain. Together with the helical arch and network of amino acids interacting with metal binding ions, the H3TH region defines a positively charged active-site DNA-binding groove in structure-specific 5' nucleases. Pssm-ID: 188626 Cd Length: 105 Bit Score: 42.68 E-value: 8.38e-05
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| H3TH_FEN1-Euk | cd09907 | H3TH domain of Flap Endonuclease-1, a structure-specific, divalent-metal-ion dependent, 5' ... |
199-227 | 1.72e-04 | |||||
H3TH domain of Flap Endonuclease-1, a structure-specific, divalent-metal-ion dependent, 5' nuclease: Eukaryotic homologs; Members of this subgroup include the H3TH (helix-3-turn-helix) domains of eukaryotic Flap endonuclease-1 (FEN1), 5' nucleases. FEN1 is involved in multiple DNA metabolic pathways, including DNA replication processes (5' flap DNA endonuclease activity and double stranded DNA 5'-exonuclease activity) and DNA repair processes (long-patch base excision repair) in eukaryotes and archaea. Interaction between FEN1 and PCNA (Proliferating cell nuclear antigen) is an essential prerequisite to FEN1's DNA replication functionality and stimulates FEN1 nuclease activity by 10-50 fold. These nucleases contain a PIN (PilT N terminus) domain with a helical arch/clamp region/I domain (not included here) and inserted within the PIN domain is an atypical helix-hairpin-helix-2 (HhH2)-like region. This atypical HhH2 region, the H3TH domain, has an extended loop with at least three turns between the first two helices, and only three of the four helices appear to be conserved. Both the H3TH domain and the helical arch/clamp region are involved in DNA binding. Studies suggest that a glycine-rich loop in the H3TH domain contacts the phosphate backbone of the template strand in the downstream DNA duplex. The nucleases within this subfamily have a carboxylate rich active site that is involved in binding essential divalent metal ion cofactors (Mg2+ or Mn2+) required for nuclease activity. The first metal binding site is composed entirely of Asp/Glu residues from the PIN domain, whereas, the second metal binding site is composed generally of two Asp residues from the PIN domain and one Asp residue from the H3TH domain. Together with the helical arch and network of amino acids interacting with metal binding ions, the H3TH region defines a positively charged active-site DNA-binding groove in structure-specific 5' nucleases. Also, FEN1 has a C-terminal extension containing residues forming the consensus PIP-box - Qxx(M/L/I)xxF(Y/F) which serves to anchor FEN1 to PCNA. Pssm-ID: 188627 [Multi-domain] Cd Length: 70 Bit Score: 40.61 E-value: 1.72e-04
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| H3TH_EXO1 | cd09908 | H3TH domain of Exonuclease-1, a structure-specific, divalent-metal-ion dependent, 5' nuclease; ... |
202-227 | 9.54e-04 | |||||
H3TH domain of Exonuclease-1, a structure-specific, divalent-metal-ion dependent, 5' nuclease; Exonuclease-1 (EXO1) is involved in multiple, eukaryotic DNA metabolic pathways, including DNA replication processes (5' flap DNA endonuclease activity and double stranded DNA 5'-exonuclease activity), DNA repair processes (DNA mismatch repair (MMR) and post-replication repair (PRR), recombination, and telomere integrity. EXO1 functions in the MMS2 error-free branch of the PRR pathway in the maintenance and repair of stalled replication forks. Studies also suggest that EXO1 plays both structural and catalytic roles during MMR-mediated mutation avoidance. Members of this subgroup include the H3TH (helix-3-turn-helix) domains of EXO1 and other similar eukaryotic 5' nucleases. These nucleases contain a PIN (PilT N terminus) domain with a helical arch/clamp region/I domain (not included here) and inserted within the PIN domain is an atypical helix-hairpin-helix-2 (HhH2)-like region. This atypical HhH2 region, the H3TH domain, has an extended loop with at least three turns between the first two helices, and only three of the four helices appear to be conserved. Both the H3TH domain and the helical arch/clamp region are involved in DNA binding. Studies suggest that a glycine-rich loop in the H3TH domain contacts the phosphate backbone of the template strand in the downstream DNA duplex. These nucleases have a carboxylate rich active site that is involved in binding essential divalent metal ion cofactors (Mg2+ or Mn2+) required for nuclease activity. The first metal binding site is composed entirely of Asp/Glu residues from the PIN domain, whereas, the second metal binding site is composed generally of two Asp residues from the PIN domain and one Asp residue from the H3TH domain. Together with the helical arch and network of amino acids interacting with metal binding ions, the H3TH region defines a positively charged active-site DNA-binding groove in structure-specific 5' nucleases. EXO1 nucleases also have C-terminal Mlh1- and Msh2-binding domains which allow interaction with MMR and PRR proteins, respectively. Pssm-ID: 188628 [Multi-domain] Cd Length: 73 Bit Score: 38.71 E-value: 9.54e-04
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