BIOCHEMICAL AND MOLECULAR ASPECTS OF VITELLOGENIN AND ITS RECEPTOR DURING THE REPRODUCTIVE CYCLE OF Dipetalogaster maxima

LEYRIA, J; AGUIRRE, SA; NAZAR, M; CANAVOSO LE

La Falda, Cordoba

Jornada; XIX Reunion Anual de la Sociedad de Biología de Córdoba; 2013

Sociedad de Biología de Córdoba

In insect females, vitellogenesis is a central event of reproductionthat elicits a massive synthesis of yolk protein precursors in the fatbody, mainly vitellogenin (Vg).Vg is taken up by developing oocytesby receptor mediated endocytosis and stored as vitellin (Vt) inyolk bodies. Unfavorable nutritional conditions may impair Vguptake by oocytes to favor follicle degeneration to an atretic stage.The aim of this work was to better understand the roles of Vg andits receptor, RVg, through the reproductive cycle of Dipetalogastermaxima, a vector of Chagas? disease. The experimental approachesincluded western blot, ELISA, RT-qPCR and in vivo Vg-FITCuptake assays. The expression of Vg in the fat body and the storesof Vt in the ovaries increased during vitellogenesis, in correlationwith an active process of Vg uptake by developing oocytes. Bycontrast, Vg synthesis and uptake diminished at early follicularatresia until it was undetectable in late atretic stages. It was shownthat the levels of RVg transcript were significantly high duringvitellogenesis, although RVg was also expressed during follicularatresia. At present, our results strongly suggested that RVg mayplay an important regulatory role in the initiation and progressionof follicular atresia.