Lipids incorporation during Bufo paracnemis vitellogenesis

VILLECCO E. I.; GENTA S. B.; HONORÉ S. M.; SÁNCHEZ RIERA A.; SÁNCHEZ S. S.

Tafí del Valle, Tucumán. Argentina.

Congreso; XVII Jornadas Científicas de la Sociedad de Biología de Tucumán; 1999

Sociedad de Biología de Tucumán.

In amphibians, yolk platellets are storage sites for biomolecules like proteins, carbohydrates, lipids, etc. The intake of these substances in the platelets of different species is not wholly understood yet. In this work, we analyze the oogenesis of Bufo paracnemis a species belongs the Buffonidae family. Vitellogenesis begins in stage III, where vitellogenin incorporation takes place from oocyte surface to yolk platelet through membrane structures. Lipids synthesized in the liver are transported to the ovary though the bloodstream and then incorporated into yolk platelets. We showed by electron microscopy multivesicular bodies with evident lipid drops inside. These lipids disappear when yolk platelets are fully grown forming a solid crystal with only one molecular packaged direction. The presence of lipid drops with proteins in multivesicular bodies is similar to that in other Buffonidae family species, like Buffo arenarum and Buffo marinus, but different from that of most known families. We believe that our results would be a characteristic fea­ture of Buffonidae family, and it would be related with the reproductive process.