Evidence of positively selected sites in mammalian alpha-defensins.
Item Type:Journal Article
Citation:Lynn, DJ, Lloyd, AT, Fares, MA, O'Farrelly, C, Evidence of positively selected sites in mammalian alpha-defensins., Molecular biology and evolution, 21, 5, 2004, 819-827
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Alpha-defensins are a family of mammalian antimicrobial peptides that exhibit variable activity against a panel of microbes, including bacteria, fungi, and enveloped viruses. We have employed a maximum-likelihood approach to detect evidence of positive selection (adaptive evolution) in the evolution of these important molecules of the innate immune response. We have identified 14 amino acid sites that are predicted to be subject to positive selection. Furthermore, we show that all these sites are located in the mature antimicrobial peptide and not in the prepropeptide region of the molecule, implying that they are of functional importance. These results suggest that mammalian alpha-defensins have been under selective pressure to evolve in response to potentially infectious challenges by fast-evolving microbes.
Type of material:Journal Article
Series/Report no:Molecular biology and evolution
Availability:Full text available
Keywords:mammalian antimicrobial peptides
Subject (TCD):Immunology, Inflammation & Infection