Premium
Action Mechanisms of the Secondary Metabolite Euplotin C: Signaling and Functional Role in Euplotes
Author(s) -
TRIELLI FRANCESCA,
CERVIA DAVIDE,
DI GIUSEPPE GRAZIANO,
RISTORI CHIARA,
KRUPPEL THOMAS,
BURLANDO BRUNO,
GUELLA GRAZIANO,
VIARENGO ALDO,
BAGNOLI PAOLA,
DELMONTE CORRADO MARIA UMBERTA,
DINI FERNANDO
Publication year - 2008
Publication title -
journal of eukaryotic microbiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.067
H-Index - 77
eISSN - 1550-7408
pISSN - 1066-5234
DOI - 10.1111/j.1550-7408.2008.00335.x
Subject(s) - biology , intracellular , metabolite , mode of action , microbiology and biotechnology , motility , vacuole , biochemistry , biophysics , cytoplasm
. Among secondary metabolites, the acetylated hemiacetal sesquiterpene euplotin C has been isolated from the marine, ciliated protist Euplotes crassus , and provides an effective mechanism for reducing populations of potential competitors through its cytotoxic properties. However, intracellular signaling mechanisms and their functional correlates mediating the ecological role of euplotin C are largely unknown. We report here that, in E. vannus (an Euplotes morphospecies that does not produce euplotin C and shares with E. crasssus the same interstitial habitat), euplotin C rapidly increases the intracellular concentration of both Ca 2+ and Na + , suggesting a generalized effect of this metabolite on cation transport systems. In addition, euplotin C does not induce oxidative stress, but modulates the electrical properties of E. vannus through an increase of the amplitude of graded action potentials. These events parallel the disassembling of the ciliary structures, the inhibition of cell motility, the occurrence of aberrant cytoplasmic vacuoles, and the rapid inhibition of phagocytic activity. Euplotin C also increases lysosomal pH and decreases lysosomal membrane stability of E. vannus . These results suggest that euplotin C exerts a marked disruption of those homeostatic mechanisms whose efficiency represents the essential prerequisite to face the challenges of the interstitial environment.