TY - JOUR
T1 - Bradykinin-related peptides and tryptophyllins in the skin secretions of the most primitive extant frog, Ascaphus truei
AU - Conlon, J. Michael
AU - Jouenne, Thierry
AU - Cosette, Pascal
AU - Cosquer, David
AU - Vaudry, Hubert
AU - Taylor, Christopher K.
AU - Abel, Peter W.
N1 - Funding Information:
The authors thank Carlos Davidson, Department of Environmental Studies, California State University, Sacramento, and Lowell Diller and Laura Burkholder, Department of Wildlife Humbolt State University, for considerable help in collection of specimens. This work was supported by an Interdisciplinary Grant (03/12-8-03-01) and a Faculty Support Grant (NP/04/02) from the United Arab Emirates University.
PY - 2005/9/1
Y1 - 2005/9/1
N2 - The tailed frog Ascaphus truei occupies a unique position in phylogeny as the most primitive extant anuran and is regarded as the sister taxon to the clade of all other living frogs. A previous study led to the isolation of eight antimicrobial peptides, termed ascaphins, from norepinephrine-stimulated skin secretions. Peptidomic analysis (HPLC separation followed by MALDI mass spectrometry and Edman degradation) of these secretions has led to the identification and structural characterization of 13 additional peptides present in relatively high concentration. In addition to bradykinin (BK; RPPGFSPFR), a C-terminally extended bradykinin (peptide RD-11; RPPGFSPFRVD), a bradykinin-like peptide (peptide AR-10; APVPGLSPFR), and a C-terminally extended form of this peptide (peptide AV-12; APVPGLSPFRVV) were obtained in pure form. These peptides produced concentration-dependent relaxation of precontracted mouse tracheal rings with a rank order of potency of BK > RD-11 > AR-10 > AV-12 but only RD-11 caused the same maximal relaxation as bradykinin. Four small peptides were also isolated from the skin secretions that contain the Pro-Trp motif that is a characteristic of the tryptophyllin family of peptides previously identified in skins of frogs of the family Hylidae. The data show that the synthesis of dermal peptides that may play a role in defense against predators arose early in the evolution of anurans.
AB - The tailed frog Ascaphus truei occupies a unique position in phylogeny as the most primitive extant anuran and is regarded as the sister taxon to the clade of all other living frogs. A previous study led to the isolation of eight antimicrobial peptides, termed ascaphins, from norepinephrine-stimulated skin secretions. Peptidomic analysis (HPLC separation followed by MALDI mass spectrometry and Edman degradation) of these secretions has led to the identification and structural characterization of 13 additional peptides present in relatively high concentration. In addition to bradykinin (BK; RPPGFSPFR), a C-terminally extended bradykinin (peptide RD-11; RPPGFSPFRVD), a bradykinin-like peptide (peptide AR-10; APVPGLSPFR), and a C-terminally extended form of this peptide (peptide AV-12; APVPGLSPFRVV) were obtained in pure form. These peptides produced concentration-dependent relaxation of precontracted mouse tracheal rings with a rank order of potency of BK > RD-11 > AR-10 > AV-12 but only RD-11 caused the same maximal relaxation as bradykinin. Four small peptides were also isolated from the skin secretions that contain the Pro-Trp motif that is a characteristic of the tryptophyllin family of peptides previously identified in skins of frogs of the family Hylidae. The data show that the synthesis of dermal peptides that may play a role in defense against predators arose early in the evolution of anurans.
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U2 - 10.1016/j.ygcen.2005.04.006
DO - 10.1016/j.ygcen.2005.04.006
M3 - Article
C2 - 15922344
AN - SCOPUS:23044466163
VL - 143
SP - 193
EP - 199
JO - General and Comparative Endocrinology
JF - General and Comparative Endocrinology
SN - 0016-6480
IS - 2
ER -