DEFA4

Defensin, alpha 4, corticostatin
PDB rendering based on 1zmm.
Available structures PDB 1zmm
Identifiers
Symbols	DEFA4; DEF4; HNP-4; HP-4; HP4; MGC120099; MGC138296
External IDs	OMIM: 601157 HomoloGene: 48059 GeneCards: DEFA4 Gene
Gene Ontology Cellular component • extracellular region • extracellular space Biological process • killing of cells of other organism • defense response to bacterium • defense response to fungus Sources: Amigo / QuickGO
Orthologs
Species	Human	Mouse
Entrez	1669	n/a
Ensembl	ENSG00000164821	n/a
UniProt	P12838	n/a
RefSeq (mRNA)	NM_001925	n/a
RefSeq (protein)	NP_001916	n/a
Location (UCSC)	Chr 8: 6.79 – 6.8 Mb	n/a
PubMed search	[1]	n/a

Defensin, alpha 4 (DEFA4), also known as neutrophil defensin 4 or HNP4, is a human defensin peptide that is encoded by the DEFA4 gene.^[1][2] The human variant of the peptide is known as human alpha defensin 4 or human neutrophil peptide 4 (HNP4). HNP4 is expressed in the granules of the neutrophil where it defends the host against bacteria^[3] and viruses.^[4]

Function

Defensins are a peptide family of cytotoxic microbicides involved in innate immunity.^[5] Members of the defensin family are distinguished by a conserved six-cysteine motif. Several human alpha defensin genes including HNP4 are clustered on chromosome 8. DEFA4 differs from other defensin genes by an extra 83-base segment that is apparently the result of a recent duplication within the coding region. HNP4 inhibits corticotropin-stimulated corticosterone production.^[1]

References

1. ^ ^{a b} "Entrez Gene: DEFA4; defensin, alpha 4, corticostatin (Homo sapiens)". http://www.ncbi.nlm.nih.gov/sites/entrez?Db=gene&Cmd=ShowDetailView&TermToSearch=1669. 
2. ^ Wu Z, Ericksen B, Tucker K, et al. (2004). "Synthesis and characterization of human alpha-defensins 4-6.". J Pept Res. 64 (3): 118–25. doi:10.1111/j.1399-3011.2004.00179.x. PMID 15317502. 
3. ^ Ericksen B, Wu Z, Lu W, Lehrer RI. (2005). "Antibacterial activity and specificity of the six human alpha defensins.". Antimicrob Agents Chemother. 49 (1): 269–75. doi:10.1128/AAC.49.1.269-275.2005. PMC 538877. PMID 15616305. http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=538877. 
4. ^ Wu Z, Cocchi F, Gentles D et al. (3 January 2005). "Human neutrophil alpha-defensin 4 inhibits HIV-1 infection in vitro". FEBS Lett 2005 January 3:162-6 579 (1): 162–6. doi:10.1016/j.febslet.2004.11.062. PMID 15620707. 
5. ^ T Ganz, M E Selsted, D Szklarek et al. (1985). "Defensins. Natural peptide antibiotics of human neutrophils.". J Clin Invest 76 (4): 1427–1435. doi:10.1172/JCI112120. PMC 424093. PMID 2997278. http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=424093. 

Further reading

• Szyk A, Wu Z, Tucker K, et al. (2006). "Crystal structures of human alpha-defensins HNP4, HD5, and HD6.". Protein Sci. 15 (12): 2749–60. doi:10.1110/ps.062336606. PMC 2242434. PMID 17088326. http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2242434. 
• Mallow EB, Harris A, Salzman N, et al. (1996). "Human enteric defensins. Gene structure and developmental expression.". J. Biol. Chem. 271 (8): 4038–45. doi:10.1074/jbc.271.8.4038. PMID 8626737. 
• Bevins CL, Jones DE, Dutra A, et al. (1996). "Human enteric defensin genes: chromosomal map position and a model for possible evolutionary relationships.". Genomics 31 (1): 95–106. doi:10.1006/geno.1996.0014. PMID 8808285. 
• Gabay JE, Scott RW, Campanelli D, et al. (1989). "Antibiotic proteins of human polymorphonuclear leukocytes.". Proc. Natl. Acad. Sci. U.S.A. 86 (14): 5610–4. doi:10.1073/pnas.86.14.5610. PMC 297672. PMID 2501794. http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=297672. 
• Davila S, Froeling FE, Tan A, et al. (2010). "New genetic associations detected in a host response study to hepatitis B vaccine.". Genes Immun. 11 (3): 232–8. doi:10.1038/gene.2010.1. PMID 20237496. 
• Kim E, Lee JE, Namkung JH, et al. (2009). "Single nucleotide polymorphisms and the haplotype in the DEFB1 gene are associated with atopic dermatitis in a Korean population.". J. Dermatol. Sci. 54 (1): 25–30. doi:10.1016/j.jdermsci.2008.12.005. PMID 19135873. 
• Milanese M, Segat L, Arraes LC, et al. (2009). "Copy number variation of defensin genes and HIV infection in Brazilian children.". J. Acquir. Immune Defic. Syndr. 50 (3): 331–3. doi:10.1097/QAI.0b013e3181945f39. PMID 19194307. 
• Palfree RG, Sadro LC, Solomon S (1993). "The gene encoding the human corticostatin HP-4 precursor contains a recent 86-base duplication and is located on chromosome 8.". Mol. Endocrinol. 7 (2): 199–205. doi:10.1210/me.7.2.199. PMID 8469233. 
• Furci L, Sironi F, Tolazzi M, et al. (2007). "Alpha-defensins block the early steps of HIV-1 infection: interference with the binding of gp120 to CD4.". Blood 109 (7): 2928–35. doi:10.1182/blood-2006-05-024489. PMID 17132727. 
• Strausberg RL, Feingold EA, Grouse LH, et al. (2002). "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. 
• Wilde CG, Griffith JE, Marra MN, et al. (1989). "Purification and characterization of human neutrophil peptide 4, a novel member of the defensin family.". J. Biol. Chem. 264 (19): 11200–3. PMID 2500436. 
• Singh A, Bateman A, Zhu QZ, et al. (1988). "Structure of a novel human granulocyte peptide with anti-ACTH activity.". Biochem. Biophys. Res. Commun. 155 (1): 524–9. doi:10.1016/S0006-291X(88)81118-5. PMID 2843187. 
• Konishi K, Gibson KF, Lindell KO, et al. (2009). "Gene expression profiles of acute exacerbations of idiopathic pulmonary fibrosis.". Am. J. Respir. Crit. Care Med. 180 (2): 167–75. doi:10.1164/rccm.200810-1596OC. PMC 2714820. PMID 19363140. http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2714820. 
• Emonts M, Vermont CL, Houwing-Duistermaat JJ, et al. (2009). "Polymorphisms in PARP, IL1B, IL4, IL10, C1INH, DEFB1 and DEFA4 in meningococcal disease in three populations.". Shock (Augusta, Ga.) 34 (1): HASH(0x2b7bc9662990). doi:10.1097/SHK.0b013e3181ce2c7d. PMID 20016407.