Identification of multiple urechistachykinin peptides, gene expression, pharmacological activity, and detection using mass spectrometric analyses.
Urechistachykinin I and II (Uru-TK I and II) are invertebrate tachykinin-related peptides (TRPs), which have been isolated from echiuroid worms. The cDNA sequence encoding the Uru-TK I and II revealed that the precursor also encoded five TRP-like peptides. Here, we report the characterization of these Uru-TK-like peptides named as Uru-TK III-VII. Northern and Southern blot analyses demonstrated that Uru-TK mRNA is localized in nerve tissue. In addition, the presence of the Uru-TK-like peptides as matured forms in the nerve tissue was detected by mass spectrometric analysis, and identified these peptides were shown to exhibit a contractile activity on cockroach hindgut that was as potent as that of Uru-TK II. Furthermore, synthetic Uru-TK-like peptide analogs which contained Met-NH2 instead of Arg-NH2 at their C-termini were shown to possess a potential to bind to a mammalian tachykinin receptor, indicating that Uru-TK-like peptides are likely to correspond to vertebrate tachykinins, except for the difference at the C-terminal residue. These findings show that Uru-TK-like peptides are essentially equivalent to Uru-TK I and II, leading to the proposal that Uru-TK-like peptides play an essential role as invertebrate tachykinin neuropeptides.
Kawada
T
T
Suntory Institute for Bioorganic Research, Wakayamadai 1-1-1, Shimamoto-cho, Mishima-gun, 618-8503, Osaka, Japan.
Masuda
K
K
Satake
H
H
Minakata
H
H
Muneoka
Y
Y
Nomoto
K
K
D000818:Animals; D015152:Blotting, Northern; D015139:Blotting, Southern; D019556:COS Cells; D003058:Cockroaches / Q000378:metabolism; D018076:DNA, Complementary / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D013058:Mass Spectrometry; D009474:Neurons / Q000378:metabolism; D009479:Neuropeptides / Q000737:chemistry* / Q000235:genetics* / Q000494:pharmacology*; D010455:Peptides / Q000737:chemistry*; D011485:Protein Binding; D021382:Protein Sorting Signals; D012333:RNA, Messenger / Q000378:metabolism; D021241:Spectrometry, Mass, Electrospray Ionization; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D013329:Structure-Activity Relationship; D014162:Transfection
D018076:DNA, Complementary; D009479:Neuropeptides; D010455:Peptides; D021382:Protein Sorting Signals; D012333:RNA, Messenger; C080807:urechistachykinin I; C080808:urechistachykinin II