Mouse beta defensin-1 is a functional homolog of human beta defensin-1.
Defensin are 3-4 kDa antimicrobial peptides of which three distinct families have been identified; alpha-defensin, beta-defensins, and insect defensins. Recent investigations have shown that beta-defensins are present in the human airways and may be relevant to the pathogenesis of cystic fibrosis (CF) lung disease. We report here the further characterization of a recently identified mouse beta-defensin gene, Defb1, sometimes referred to as mBD-1, which is homologous to the human airway beta defensin hBD-1. We report that Defb1 is expressed in a variety of tissues including the airways and, similar to hBD-1, is not upregulated by lipopolysaccharide (LPS). Defb1 was found to consist of two small exons separated by a 16-kb intron and cytogenetic, and physical mapping linked it to the alpha defensin gene cluster on mouse Chromosome (Chr) 8. Functional studies demonstrate that, like hBD-1, Defb1 demonstrates a salt-sensitive antimicrobial activity against Pseudomonas aeruginosa. Of relevance to CF lung disease is the fact that neither the hBD-1 nor the mBD-1 peptides are active against Burkholderia cepacia.
Morrison
G M
GM
MRC Human Genetics Unit, Western General Hospital, Edinburgh, EH4 2XU, Scotland, UK.
Davidson
D J
DJ
Kilanowski
F M
FM
Borthwick
D W
DW
Crook
K
K
Maxwell
A I
AI
Govan
J R
JR
Dorin
J R
JR
D000595:Amino Acid Sequence; D000818:Animals; D001798:Blood Proteins / Q000235:genetics*; D002874:Chromosome Mapping; D023082:Defensins; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D051379:Mice; D008810:Mice, Inbred C57BL; D008969:Molecular Sequence Data; D015183:Restriction Mapping; D023083:beta-Defensins
D001798:Blood Proteins; C406407:DEFB1 protein, human; D023082:Defensins; D023083:beta-Defensins