Synergistic Action of Actinoporin Isoforms from the Same Sea Anemone Species Assembled into Functionally Active Heteropores


Autoria(s): Rivera de la Torre, Esperanza; García Linares, Sara; Alegre Cebollada, Jorge; Lacadena, Javier; Gavilanes, José G.; Martínez del Pozo, Alvaro
Data(s)

2016

31/12/1969

Resumo

Among the toxic polypeptides secreted in the venom of sea anemones, actinoporins are the pore-forming toxins whose toxic activity relies on the formation of oligomeric pores within biological membranes. Intriguingly, actinoporins appear as multigene families that give rise to many protein isoforms in the same individual displaying high sequence identities but large functional differences. However, the evolutionary advantage of producing such similar isotoxins is not fully understood. Here,using sticholysins I and II (StnI and StnII) from the sea anemone Stichodactyla helianthus, it is shown that actinoporin isoforms can potentiate each other’s activity. Through hemolysis and calcein releasing assays, it is revealed that mixtures of StnI and StnII are more lytic than equivalent preparations of the corresponding isolated isoforms. It is then proposed that this synergy is due to the assembly of heteropores because (i) StnI and StnII can be chemically cross-linked at the membrane and (ii) the affinity of sticholysin mixtures for the membrane is increased with respect to any of them acting in isolation, as revealed by isothermal titration calorimetry experiments. These results help us understand the multigene nature of actinoporins and may be extended to other families of toxins that require oligomerization to exert toxicity.

Formato

application/pdf

Identificador

http://eprints.ucm.es/38143/1/proofDefinitivas.pdf

Idioma(s)

en

Publicador

ASBMB American Society for Biochemistry and Molecular Biology

Relação

http://eprints.ucm.es/38143/

http://www.jbc.org/content/early/2016/04/27/jbc.M115.710491.full.pdf?sid=fa51db07-c9d2-4e56-b9c2-8d6b1009cea9

10.1074/jbc.M115.710491

BFU2012-32404

RYC-2014-16604

Direitos

info:eu-repo/semantics/embargoedAccess

Palavras-Chave #Bioquímica
Tipo

info:eu-repo/semantics/article

PeerReviewed