Host‐defence peptide profiles of the skin secretions of interspecific hybrid tree frogs and their parents, female Litoria splendida and male Litoria caerulea

Abstract

The skin of amphibians contains a rich chemical arsenal that forms an integral part of their defence systems, and also assists with the regulation of dermal physiological action. In response to a variety of stimuli, host-defence compounds are secreted from specialized dermal glands onto the dorsal surface and into the gut of the amphibian. Many of these defence compounds are peptides. Some of the peptides are vasodilators, whereas others show antimicrobial activity or inhibit the formation of nitric oxide by neuronal nitric oxide synthase (nNOS) [1][2][3][4][5].Amphibian skin-peptide profiles are not only typically characteristic of individual species, but can also distinguish subspecies or particular populations within a species [4][5][6][7][8], despite seasonal variation in the skinpeptide content of some amphibians [4,5].Many species of amphibians hybridize naturally with some forming extensive zones of hybridization [9][10][11][12][13][14][15][16][17][18][19][20]. Five healthy adult female first-generation hybrid tree frogs were produced by interspecific breeding of closely related tree frogs Litoria splendida and L. caerulea in a cage containing large numbers of males and females of both species. Phylogenetic analysis of mitochondrial DNA sequences established the female parent to be L. splendida. The peptide profile of the hybrid frogs included the neuropeptide caerulein, four antibiotics of the caerin 1 family and several neuronal nitric oxide synthase inhibitors of the caerin 1 and 2 classes of peptides. The skin secretions of the hybrids contained some peptides common to only one parent, some produced by both parental species, and four peptides expressed by the hybrids but not the parental species.Abbreviations Ca 2+ CaM, calcium calmodulin; nNOS, neuronal nitric oxide synthase.

Hybrid advantage in skin peptide immune defenses of water frogs (Pelophylax esculentus) at risk from emerging pathogens

“…of P. esculentus compared to its parent species (Tunner and Nopp, 1979;Semlitsch and Reyer, 1992;Fioramonti et al, 1997;Hotz et al, 1999). Pukala et al (2006) examined the peptide repertoire of hybrid Australian tree frogs. When a female Litoria splendida and a male L. caerulea were mated, F 1 hybrid offspring expressed skin peptides found in both parents, and four unique peptides not previously described.…”

“…To help unravel outstanding questions about the structural and functional diversity of AMPs, hybrid amphibian systems are valuable, but largely unstudied (Parris, 2004;Pukala et al, 2006). The Pelophylax (formerly Rana) complex presents an ideal system to study if and how hybridization affects AMP defenses.…”

Host Defense Skin Peptides Vary with Color Pattern in the Highly Polymorphic Red-Eyed Treefrog

“…Variation in amphibian defense chemicals (e.g., alkaloids and skin peptides) have been included in the phylogenetic reconstruction of dendrobatids (Grant et al, 2006), bufonids (Wittliff, 1964;Pollard et al, 1973), ranids (Conlon, 2008), hylids (Wabnitz et al, 1999), and species in the genus Pelophylax (Daum et al, 2012). At finer spatial scales, the Australian tree frog Litoria rubella, displays a clinal north-south distribution in peptide profiles that correlates with pigmentation (Steinborner et al, 1996;Apponyi et al, 2004;Pukala et al, 2006). In another example, peptide variation in Litoria caerulea reflects phylogenetic relationships among populations across regions (Donnellan et al, 2000).…”

N-terminal tagging strategy forDe Novosequencing of short peptides by ESI-MS/MS and MALDI-MS/MS

“…The peptide activity range is extremely broad: from antimicrobial, antitumor, fungicide activities to neuropeptides and analgesic peptides [2].…”

“…A nuran skin is a well-known source of bioactive peptides [1][2][3] responsible for high immunity of these amphibians [4]. The peptide activity range is extremely broad: from antimicrobial, antitumor, fungicide activities to neuropeptides and analgesic peptides [2].…”