Fig. 1.
Genomic organization of avian and mammalian defensins and corresponding mature peptide structures. Differential transcription and subsequent translation of exons (E1–4) into the 5′ and 3′ untranslated regions (UTR) and peptide encoding regions for: signal peptide (diagonal striped bars), propiece (dotted bars) and mature peptide (solid blue bars; red and green bars depict homo- or heterodimers based formation of a single cyclic θ-defensin peptide). Despite differences in genomic organization, 3D structures of mature avian β-defensins and mammalian α- and β-defensins are very similar: AvBD103b, king penguin avian β-defensin 103b (Sphenicin-2); hBD-1, human β-defensin-1; HD-5, human α-defensin-5; RK-1, rabbit kidney defensin-1; RTD-1, rhesus θ-defensin-1. (For interpretation of the references to colour in this figure legend, the reader is referred to the web version of the article.)