INVESTIGADORES
VALENTINUZZI veronica Sandra
congresos y reuniones científicas
Título:
Host-vector-parasite temporal interaction: a zoom in the role of light and host in the Chagas disease vector, Triatoma infestans
Autor/es:
VALENTINUZZI VS; LOPEZ PJ; RALPH MR
Lugar:
Braganza Paulista, SP
Reunión:
Simposio; XIII Latin American Symposium on Chronobiology-LASC; 2015
Resumen:
The classic model of circadian rhythm generation and entrainment presents a species-specific clock entrained by one or more 24 hour Zeitgebers. Whereas the primary entraining cycle throughout phylogeny is light and dark (LD), numerous non-photic synchronizers (e.g. food, temperature, activity, social interactions) may become more significant under certain circumstances. The host-vector-parasitic relationship represents a circumstance where LD may have ceased to be the primary Zeitgeber, and been replaced by the non-photic influence of the host. Triatoma infestans (kissing bug) is the main vector responsible for the transmission of Trypanosoma cruzi, the causative agent of Chagas Disease, a chronic trypanosomiasis infecting 10 million people world-wide. Different aspects of this haematophagous bug´s life have been described as temporally modulated. Some expressed at the individual level (e.g., locomotor activity) while others become evident in populations (e.g., eclosion). Previous data revealed a nocturnal bimodal activity rhythm. However, interestingly, these insects feed on both diurnal and nocturnal species, during each host?s quiescent time. As the hosts are also their major predators, kissing bugs are subjected to dual selective pressures from a single source. Therefore, synchronization with the host?s behavior may become even more critical to the insects? survival. We show that nonphotic signals linked to the host eclipse the role of LD as the primary Zeitgeber, although light still inhibits locomotor behavior directly. In nature, this combination provides the insect with great flexibility in organizing physiology and behavior: anticipating a quiescent host or avoiding its potential predation while remaining directly responsive to immediate environmental conditions.