Prolonged signalling and trafficking of the bradykinin B2 receptor stimulated with the amphibian peptide maximakinin: Insight into the endosomal inactivation of kinins

Abstract

Maximakinin, a 19-residue peptide from the amphibian Bombina maxima, incorporates the full sequence of bradykinin (BK) at its C-terminus with a hydrophilic 10-residue N-terminal Maximakinin is the first known natural kinin sequence that elicits a prolonged cellular signalling, thus suggesting a possible basis for a venomous action and a naturally selected one for the design of B 2 R-transported biotechnological cargoes.

Inhibitory effects of cytoskeleton disrupting drugs and GDP-locked Rab mutants on bradykinin B2 receptor cycling

“…The recycling of B 2 R-GFP is conveniently assessed 3 h after stimulation with BK, a fragile peptide that is rapidly cleared by different pathways in both the serum-containing culture medium and in endosomes [5] (Fig. 6, top …”

“…Thus, the B 2 R combines with either type of non-visual -arrestins and the ligand-B 2 R--arrestin complex gets translocated into endosomes [1,2]. The fusion protein B 2 Rgreen fluorescent protein (B 2 R-GFP) -arrestins conjugated to fluorescent proteins and BK sequences that were extended with fluorophores were instrumental in modeling the BK-induced endocytosis, but also its recycling to the cell surface and the persistence of the ternary agonistreceptor--arrestin complexes in intracellular structures [3][4][5] (and literature cited herein).…”

“…However, the BK-stimulated B 2 Rs are essentially completely recycled to the cell surface as a function of time, unless the agonist has an altered structure that confers resistance to proteolytic breakdown. In this case, the length of the B 2 R internalization and the duration of signaling are remarkably prolonged, and the secondary down-regulation of the receptors becomes prominent [2,5].…”

Ex Vivo Smooth Muscle Pharmacological Effects of a Novel Bradykinin-Related Peptide, and Its Analogue, from Chinese Large Odorous Frog, Odorrana livida Skin Secretions

“…Of interest is that only the leucine residue substitution at position 8 of BK would cause such an astonishing function loss. Leucine 1 is a common substitution occurred in BRPs, compared with valine substation at position 1, it normally exhibits moderate agonistic effect of BK [26]. As the fact that Leu8-BK was reported as a BK receptor antagonist [27], we performed further experiments to examine whether RAP-L1, T6-BK and its analogue RAP-L1, T6, L8-BK could inhibit BK-induced relax on rat tail artery smooth muscle, the results revealed that, as expected, RAP-L1, T6-BK did not show BK inhibition property (Figure S1), but RAP-L1, T6, L8-BK significantly reduced BK relaxation activity on rat tail artery nearly 50% in the concentration range 10 −8 M–10 −5 M. These data suggested that although this novel BRP has a three residues -RAP- extension and leucine 1, threonine 6 substitutions, the leucine 8 still plays the essential and dominant role in reversing the BK’s effect.…”

Vasopeptidase-activated latent ligands of the histamine receptor-1

“…Endosomal BK degradation obligatorily precedes the dissociation of β-arrestins from the B 2 R and receptor recycling to the cell surface, as shown by several inactivation-resistant B 2 R agonists that promote the persistence of this intracellular complex for at least 12 h and prolonged signaling [6,7]. Fluorophore conjugated analogs (carboxyfluorescein-or AlexaFluor-350-ε-aminocaproyl-BK) model the intracellular inactivation of the kinin, notably because the inhibitor of the proton pump V-ATPase, bafilomycin A1, prevents the time-dependent disappearance of the fluorescent peptides in endosomes of B 2 Rexpressing cells [8,9].…”