Exonuclease 1

Exonuclease 1
Identifiers
Symbols	EXO1; HEX1; hExoI
External IDs	OMIM: 606063 MGI: 1349427 HomoloGene: 31352 GeneCards: EXO1 Gene
Gene Ontology Molecular function • DNA binding • endonuclease activity • ribonuclease H activity • exonuclease activity • protein binding • 5'-3' exonuclease activity • 5'-3' exodeoxyribonuclease activity • structure-specific DNA binding • single-stranded DNA specific 5'-3' exodeoxyribonuclease activity • metal ion binding • flap endonuclease activity • double-stranded DNA specific 5'-3' exodeoxyribonuclease activity Cellular component • nucleus Biological process • humoral immune response mediated by circulating immunoglobulin • DNA repair • mismatch repair • mismatch repair • mismatch repair • mismatch repair • DNA recombination • meiosis • somatic hypermutation of immunoglobulin genes • isotype switching Sources: Amigo / QuickGO
RNA expression pattern
More reference expression data
Orthologs
Species	Human	Mouse
Entrez	9156	26909
Ensembl	ENSG00000174371	ENSMUSG00000039748
UniProt	Q9UQ84	Q9QZ11
RefSeq (mRNA)	NM_003686.4	NM_012012.4
RefSeq (protein)	NP_003677.4	NP_036142.2
Location (UCSC)	Chr 1: 242.01 – 242.06 Mb	Chr 1: 177.81 – 177.84 Mb
PubMed search	[1]	[2]

Exonuclease 1 is an enzyme that in humans is encoded by the EXO1 gene.

This gene encodes a protein with 5' to 3' exonuclease activity as well as an RNase H activity (endonuclease activity cleaving RNA on DNA/RNA hybrid). It is similar to the Saccharomyces cerevisiae protein Exo1 which interacts with Msh2 and which is involved in DNA mismatch repair and homologous recombination. Alternative splicing of this gene results in three transcript variants encoding two different isoforms.

Interactions

Exonuclease 1 has been shown to interact with MSH2 and MLH1.

Further reading

• Liberti SE, Rasmussen LJ (2005). "Is hEXO1 a cancer predisposing gene?". Mol. Cancer Res. 2 (8): 427–32. PMID 15328369. 
• Holle GE (1985). "[Pathophysiology of ulcer disease]". Langenbecks Archiv für Chirurgie 366: 81–7. PMID 2414623. 
• Bonaldo MF, Lennon G, Soares MB (1997). "Normalization and subtraction: two approaches to facilitate gene discovery.". Genome Res. 6 (9): 791–806. doi:10.1101/gr.6.9.791. PMID 8889548. 
• Tishkoff DX, Amin NS, Viars CS, et al. (1998). "Identification of a human gene encoding a homologue of Saccharomyces cerevisiae EXO1, an exonuclease implicated in mismatch repair and recombination.". Cancer Res. 58 (22): 5027–31. PMID 9823303. 
• Qiu J, Qian Y, Chen V, et al. (1999). "Human exonuclease 1 functionally complements its yeast homologues in DNA recombination, RNA primer removal, and mutation avoidance.". J. Biol. Chem. 274 (25): 17893–900. doi:10.1074/jbc.274.25.17893. PMID 10364235. 
• Lee BI, Wilson DM (2000). "The RAD2 domain of human exonuclease 1 exhibits 5' to 3' exonuclease and flap structure-specific endonuclease activities.". J. Biol. Chem. 274 (53): 37763–9. doi:10.1074/jbc.274.53.37763. PMID 10608837. 
• Rasmussen LJ, Rasmussen M, Lee B, et al. (2000). "Identification of factors interacting with hMSH2 in the fetal liver utilizing the yeast two-hybrid system. In vivo interaction through the C-terminal domains of hEXO1 and hMSH2 and comparative expression analysis.". Mutat. Res. 460 (1): 41–52. doi:10.1016/S0921-8777(00)00012-4. PMID 10856833. 
• Wu Y, Berends MJ, Post JG, et al. (2001). "Germline mutations of EXO1 gene in patients with hereditary nonpolyposis colorectal cancer (HNPCC) and atypical HNPCC forms.". Gastroenterology 120 (7): 1580–7. doi:10.1053/gast.2001.25117. PMID 11375940. 
• Schmutte C, Sadoff MM, Shim KS, et al. (2001). "The interaction of DNA mismatch repair proteins with human exonuclease I.". J. Biol. Chem. 276 (35): 33011–8. doi:10.1074/jbc.M102670200. PMID 11427529. 
• Jäger AC, Rasmussen M, Bisgaard HC, et al. (2001). "HNPCC mutations in the human DNA mismatch repair gene hMLH1 influence assembly of hMutLalpha and hMLH1-hEXO1 complexes.". Oncogene 20 (27): 3590–5. doi:10.1038/sj.onc.1204467. PMID 11429708. 
• Genschel J, Bazemore LR, Modrich P (2002). "Human exonuclease I is required for 5' and 3' mismatch repair.". J. Biol. Chem. 277 (15): 13302–11. doi:10.1074/jbc.M111854200. PMID 11809771. 
• Lee Bi BI, Nguyen LH, Barsky D, et al. (2002). "Molecular interactions of human Exo1 with DNA.". Nucleic Acids Res. 30 (4): 942–9. doi:10.1093/nar/30.4.942. PMC 100345. PMID 11842105. http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=100345. 
• Sun X, Zheng L, Shen B (2002). "Functional alterations of human exonuclease 1 mutants identified in atypical hereditary nonpolyposis colorectal cancer syndrome.". Cancer Res. 62 (21): 6026–30. PMID 12414623. 
• Strausberg RL, Feingold EA, Grouse LH, et al. (2003). "Generation and initial analysis of more than 15,000 full-length human and mouse cDNA sequences.". Proc. Natl. Acad. Sci. U.S.A. 99 (26): 16899–903. doi:10.1073/pnas.242603899. PMC 139241. PMID 12477932. http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=139241. 
• Jagmohan-Changur S, Poikonen T, Vilkki S, et al. (2003). "EXO1 variants occur commonly in normal population: evidence against a role in hereditary nonpolyposis colorectal cancer.". Cancer Res. 63 (1): 154–8. PMID 12517792. 
• Sharma S, Sommers JA, Driscoll HC, et al. (2003). "The exonucleolytic and endonucleolytic cleavage activities of human exonuclease 1 are stimulated by an interaction with the carboxyl-terminal region of the Werner syndrome protein.". J. Biol. Chem. 278 (26): 23487–96. doi:10.1074/jbc.M212798200. PMID 12704184. 
• Alam NA, Gorman P, Jaeger EE, et al. (2004). "Germline deletions of EXO1 do not cause colorectal tumors and lesions which are null for EXO1 do not have microsatellite instability.". Cancer Genet. Cytogenet. 147 (2): 121–7. doi:10.1016/S0165-4608(03)00196-1. PMID 14623461. 
• Genschel J, Modrich P (2004). "Mechanism of 5'-directed excision in human mismatch repair.". Mol. Cell 12 (5): 1077–86. doi:10.1016/S1097-2765(03)00428-3. PMID 14636568.