title: Components of the peptidome and transcriptome persist in lin wa pi: the dried skin of the Heilongjiang brown frog (Rana amurensis) as used in traditional Chinese medicine.
abstract: Although the ancient practice of traditional Chinese medicine (TCM) utilizes predominantly herbal ingredients, many of which are now the subject of intense scientific scrutiny, significant quantities of animal tissue-derived materials are also employed. Here we have used contemporary molecular techniques to study the material known as lin wa pi, the dried skin of the Heilongjiang brown frog, Rana amurensis, that is used commonly as an ingredient of many medicines, as a general tonic and as a topical antimicrobial/wound dressing. Using a simple technology that has been developed and validated over several years, we have demonstrated that components of both the skin granular gland peptidome and transcriptome persist in this material. Interrogation of the cDNA library constructed from the dried skin by entrapment and amplification of polyadenylated mRNA, using a "shotgun" primer approach and 3'-RACE, resulted in the cloning of cDNAs encoding the precursors of five putative antimicrobial peptides. Two (ranatuerin-2AMa and ranatuerin-2AMb) were obvious homologs of a previously described frog skin peptide family, whereas the remaining three were of sufficient structural novelty to be named amurins 1-3. Mature peptides were each identified in reverse phase HPLC fractions of boiling water extracts of skin and their structures confirmed by MS/MS fragmentation sequencing. Components of traditional Chinese medicines of animal tissue origin may thus contain biologically active peptides that survive the preparation procedures and that may contribute to therapeutic efficacy.
authors.affiliation: School of Pharmacy, Queen's University, Belfast BT9 7BL, Northern Ireland, UK.
authors.forename: Mei
authors.initials: M
authors.lastname: Zhou
authors.forename: Yang
authors.initials: Y
authors.lastname: Liu
authors.forename: Tianbao
authors.initials: T
authors.lastname: Chen
authors.forename: Xuexun
authors.initials: X
authors.lastname: Fang
authors.forename: Brian
authors.initials: B
authors.lastname: Walker
authors.forename: Chris
authors.initials: C
authors.lastname: Shaw
mesh_terms: D000388:Air; D000595:Amino Acid Sequence; D000818:Animals; D023181:Antimicrobial Cationic Peptides / Q000235:genetics; D001001:Anura / Q000145:classification / Q000235:genetics* / Q000378:metabolism; D001483:Base Sequence; D002851:Chromatography, High Pressure Liquid; D003001:Cloning, Molecular; D003890:Desiccation; D008516:Medicine, Chinese Traditional; D008969:Molecular Sequence Data; D009842:Oligopeptides / Q000235:genetics; D010455:Peptides / Q000737:chemistry*; D020543:Proteome / Q000235:genetics*; D012867:Skin / Q000737:chemistry*; D014158:Transcription, Genetic
chemical_list: D023181:Antimicrobial Cationic Peptides; D009842:Oligopeptides; D010455:Peptides; D020543:Proteome; C519183:amurin-3 protein, Rana amurensis