Novel bradykinins and their precursor cDNAs from European yellow-bellied toad (Bombina variegata) skin.
Two novel bradykinin-related peptides (Ala3,Thr6)-bradykinin and (Val1,Thr3,Thr6)-bradykinin, were identified by a systematic sequencing study of peptides in the defensive skin secretion of the yellow-bellied toad, Bombina variegata. These peptides are the first amphibian skin bradykinins to exhibit amino acid substitutions at the Pro3 position of the bradykinin nonapeptide. Previously reported bradykinins from other Bombina species were not detected. Respective precursor cDNAs, designated BVK-1 and BVK-2, respectively, were cloned from a skin library by 3'- and 5'-RACE reactions. BVK-1 contained an open-reading frame of 97 amino acids encoding a single copy of (Ala3,Thr6)-bradykinin and similarly, the open-reading frame of BVK-2 consisted of 96 amino acids encoding a single copy of (Val1,Thr3,Thr6)-bradykinin. Synthetic replicates of each novel bradykinin were found to be active on mammalian arterial and small intestinal smooth muscle preparations. The structural diversity of bradykinins in amphibian defensive skin secretions may be related to defence against specific predators.
Chen
Tianbao
T
School of Biomedical Sciences, University of Ulster, Coleraine, Northern Ireland, UK; The Institute of Biotechnology, Fuzhou University, Fujian Province, People's Republic of China.
Orr
David F
DF
Bjourson
Anthony J
AJ
McClean
Stephen
S
O'Rourke
Martin
M
Hirst
David G
DG
Rao
Pingfan
P
Shaw
Chris
C
D000595:Amino Acid Sequence; D000818:Animals; D001001:Anura; D001483:Base Sequence; D001920:Bradykinin / Q000235:genetics* / Q000378:metabolism / Q000494:pharmacology; D018076:DNA, Complementary; D008297:Male; D008969:Molecular Sequence Data; D009130:Muscle, Smooth / Q000502:physiology; D011498:Protein Precursors / Q000235:genetics; D051381:Rats; D017208:Rats, Wistar; D016415:Sequence Alignment; D012867:Skin / Q000378:metabolism
D018076:DNA, Complementary; D011498:Protein Precursors; D001920:Bradykinin