Paracrine regulation during Xenopus laevis oogenesis

SERRANO MA; SÁNCHEZ SS

Rosario, Santa Fe

Congreso; L Annual Meeting Argentine Society for Biochemistry and Molecular Biology; 2014

Argentine Society for Biochemistry and Molecular Biology

Oogenesis in vertebrates has been characterized as the result of a regulation between different signaling systems such as endocrine and juxtacrine. Paracrine factors belonging to the TGF-b superfamily -like BMPs- have been identified as fundamental for the progress of oogenesis. Not much is known about paracrine regulation during oogenesis in oviparous vertebrates, which has the complexity of the three different stages: previtellogenesis, vitellogenesis and maturation. Amphibian vitellogenesis is a well-controlled process characterized by hepatic production of the glycoprotein vitellogenin (VTG) that is transported via the bloodstream to the ovary where it is incorporated by oocytes. In previous work we have demonstrated that in Xenopus laevis ovary, VTG uptake is regulated not only by endocrine and juxtacrine signaling but also by an interplay between them. In this work we delve deeper into the study of paracrine regulation assessing the role of the TGF-b signaling via Smad2/3 during X. laevis oogenesis. To analyze the role of this pathway in the progression of oogenesis, we performed different assays with the anti-TGFβRII antibody, a BMP pathway inhibitor and a gap junction uncoupling agent. The results showed that TGF-b signaling might be implicated in X. laevis oogenesis, a complex process coordinated by a cross talk between the molecules of different signaling pathways.