title: Peptide Tyrosine Arginine, a potent immunomodulatory peptide isolated and structurally characterized from the skin secretions of the dusky gopher frog, Rana sevosa.
abstract: An octadecapeptide was isolated from the skin secretions of the dusky gopher frog (Rana sevosa) on the basis of histamine release from rat peritoneal mast cells. This peptide was purified to homogeneity by HPLC and found to have the following primary structure, YLKGCWTKSYPPKPCFSR, using both Edman degradation chemistry and peptide sequencing using high-resolution mass spectrometry (Q-TOF MS). The peptide, named peptide Tyrosine Arginine (pYR) shares 77.8% homology with peptide Leucine Arginine (pLR). The effects of the natural amidated peptide, non-amidated peptide and C-loop region of pYR on granulopoiesis and neutrophil apoptosis were investigated. All three analogues inhibited the early development of granulocyte macrophage colonies from bone marrow stem cells but did not induce apoptosis of the end stage granulocytes, the mature neutrophil. Thus, pYR is a novel member of an important and emerging new class of amphibian peptides with hemopoietic actions.
authors.affiliation: School of Biomedical Science, University of Ulster, Northan Ireland, Coleraine BT52 1SA, UK. c.graham1@ulster.ac.uk
authors.forename: Ciaren
authors.initials: C
authors.lastname: Graham
authors.forename: Alexandra E
authors.initials: AE
authors.lastname: Irvine
authors.forename: Stephen
authors.initials: S
authors.lastname: McClean
authors.forename: Stephen C
authors.initials: SC
authors.lastname: Richter
authors.forename: Peter R
authors.initials: PR
authors.lastname: Flatt
authors.forename: Chris
authors.initials: C
authors.lastname: Shaw
mesh_terms: D000595:Amino Acid Sequence; D029845:Amphibian Proteins / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology*; D000818:Animals; D003114:Colony-Forming Units Assay; D006098:Granulocytes / Q000187:drug effects; D006636:Histamine Release / Q000187:drug effects; D007155:Immunologic Factors / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology*; D008264:Macrophages / Q000187:drug effects; D008297:Male; D008407:Mast Cells / Q000187:drug effects; D008969:Molecular Sequence Data; D010455:Peptides / Q000737:chemistry / Q000302:isolation & purification; D011898:Ranidae / Q000378:metabolism; D051381:Rats; D012867:Skin / Q000378:metabolism
chemical_list: D029845:Amphibian Proteins; D007155:Immunologic Factors; D010455:Peptides; C503958:peptide tyrosine arginine, Rana sevosa