From Wikipedia, the free encyclopedia
Jump to: navigation, search
Defensin, beta 103B
Protein DEFB103A PDB 1kj6.png
PDB rendering based on 1kj6.
Available structures
PDB Ortholog search: PDBe, RCSB
Symbols DEFB103B ; BD-3; DEFB-3; DEFB103; DEFB3; HBD-3; HBD3; HBP-3; HBP3
External IDs OMIM606611 MGI2675345 HomoloGene10256 GeneCards: DEFB103B Gene
Species Human Mouse
Entrez 55894 244332
Ensembl ENSG00000176797 ENSMUSG00000046354
UniProt P81534 Q7TNV9
RefSeq (mRNA) NM_018661 NM_183026
RefSeq (protein) NP_061131 NP_898847
Location (UCSC) Chr 8:
7.29 – 7.29 Mb
Chr 8:
19.19 – 19.2 Mb
PubMed search [1] [2]

Beta-defensin 103 is a protein that in humans is encoded by the DEFB103A gene.[1][2][3]


Defensins form a family of microbicidal and cytotoxic peptides made by neutrophils. Members of the defensin family are highly similar in protein sequence. This gene encodes defensin, beta 103B, which has broad spectrum antimicrobial activity and may play an important role in innate epithelial defense.[3]

In dogs, the product of the same genetic locus, β-Defensin 103, also plays a role in pigmentation, being an agonist of the melanocortin 1 receptor.[4]


  1. ^ Jia HP, Schutte BC, Schudy A, Linzmeier R, Guthmiller JM, Johnson GK, Tack BF, Mitros JP, Rosenthal A, Ganz T, McCray PB Jr (Mar 2001). "Discovery of new human beta-defensins using a genomics-based approach". Gene 263 (1–2): 211–8. doi:10.1016/S0378-1119(00)00569-2. PMID 11223260. 
  2. ^ Harder J, Bartels J, Christophers E, Schroder JM (Feb 2001). "Isolation and characterization of human beta -defensin-3, a novel human inducible peptide antibiotic". J Biol Chem 276 (8): 5707–13. doi:10.1074/jbc.M008557200. PMID 11085990. 
  3. ^ a b "Entrez Gene: DEFB103A defensin, beta 103A". 
  4. ^ Candille SI, Kaelin CB, Cattanach BM, Yu B, Thompson DA, Nix MA, Kerns JA, Schmutz SM, Millhauser GL, Barsh GS (November 2007). "A -defensin mutation causes black coat color in domestic dogs". Science 318 (5855): 1418–23. doi:10.1126/science.1147880. PMC 2906624. PMID 17947548. 

Further reading[edit]