« Previous Abstract"Isolation and structural characterization of two water-borne pheromones from Euplotes crassus, a ciliate commonly known to carry membrane-bound pheromones"    Next Abstract"Bioactive molecules from ciliates: Structure, activity, and applicative potential" »

Exp Cell Res

Title:		"Cell aging-induced methionine oxidation causes an autocrine to paracrine shift of the pheromone activity in the protozoan ciliate, Euplotes raikovi"
Author(s):		Alimenti C; Vallesi A; Luporini P; Buonanno F; Ortenzi C;
Address:		"Dipartimento di Scienze Ambientali e Naturali, University of Camerino, 62032 Camerino (MC), Italy"
Journal Title:		Exp Cell Res
Year:		2012
Volume:		20111021
Issue:		2
Page Number:		144 - 151
DOI:		10.1016/j.yexcr.2011.10.011
ISSN/ISBN:		1090-2422 (Electronic) 0014-4827 (Linking)
Abstract:		"Ciliates of the genus Euplotes rely on the autocrine (self) and paracrine (non-self) activities of their water-borne protein pheromones to control the two fundamental phenomena of their life cycle, i.e. vegetative (mitotic) growth and sex manifested as cell union in mating pairs. We observed that cell aging determines the synthesis of increasing concentrations of pheromones that are oxidized at the level of methionine residues which are more exposed on the molecular surface. The oxidized form of the E. raikovi pheromone Er-1 was purified and its interactions with its source cells were shown no longer to be of autocrine type directed to promote cell growth, but changed to interactions of the paracrine type directed to induce cell unions in mating pairs of the selfing type (i.e. involving genetically identical cells). These pairs generate viable offspring, like pairs formed between genetically different cells. It was therefore concluded that aging cells may paradoxically gain beneficial effects from the synthesis of oxidized forms of their pheromones. By undergoing mating in response to the interactions with these forms, they can re-initiate a new life cycle and, in fact, rejuvenate"
Keywords:		Amino Acid Sequence *Autocrine Communication Euplotes/*metabolism Membrane Proteins/*metabolism Methionine/*metabolism Oxidation-Reduction *Paracrine Communication Pheromones/*metabolism Protozoan Proteins/*metabolism;
Notes:		"MedlineAlimenti, Claudio Vallesi, Adriana Luporini, Pierangelo Buonanno, Federico Ortenzi, Claudio eng Research Support, Non-U.S. Gov't 2011/11/01 Exp Cell Res. 2012 Jan 15; 318(2):144-51. doi: 10.1016/j.yexcr.2011.10.011. Epub 2011 Oct 21"