Isolation and characterization of novel tachykinins from the posterior salivary gland of the common octopus Octopus vulgaris.
Two novel tachykinins (OctTK-I: Lys-Pro-Pro-Ser-Ser-Ser-Glu-Phe-Ile-Gly-Leu-Met-NH(2) and OctTK-II: Lys-Pro-Pro-Ser-Ser-Ser-Glu-Phe-Val-Gly-Leu-Met-NH(2)) were isolated from the posterior salivary gland of the octopus (Octopus vulgaris) using a contraction assay of the carp rectum. These peptides had in common the pentapeptide sequence -Phe-X-Gly-Leu-Met-NH(2) at the C-terminal and induced immediate contractions on the carp rectum and the guinea-pig ileum. cDNAs encoding their precursor proteins were cloned. The OctTK gene was expressed in the posterior salivary gland and the expression was localized in mucus-secreting cells of the gland. The results suggested that OctTKs might be secreted as a venomous substance acting on vertebrates such as fishes, which are the prey or natural enemies of the octopus.
Kanda
Atsuhiro
A
Suntory Institute for Bioorganic Research, 1-1-1 Wakayamadai, Shimamotocho, Mishimagun, Osaka 618-8503, Japan.
Iwakoshi-Ukena
Eiko
E
Takuwa-Kuroda
Kyoko
K
Minakata
Hiroyuki
H
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D015139:Blotting, Southern; D003001:Cloning, Molecular; D018076:DNA, Complementary; D017403:In Situ Hybridization; D008969:Molecular Sequence Data; D049831:Octopodiformes; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012469:Salivary Glands / Q000737:chemistry*; D021241:Spectrometry, Mass, Electrospray Ionization; D015320:Tachykinins / Q000737:chemistry / Q000302:isolation & purification*
D018076:DNA, Complementary; D015320:Tachykinins