Nava DEKEL (Israel)
Prof. Nava Dekel earned her PhD degree at Tel Aviv University (1977). After a postdoctoral period at the Rockefeller University (1977-1979) and at the New York University (1980-1981), she returned to Israel and joined the Weizmann Institute of Science in the Department of Hormone Research, which she headed from 1992-1995. From 2005-2011, she headed the Department of Biological Regulation and was the Director of the Willner Family Center for Vascular Biology. She was promoted to Full Professor and the incumbent of the Philip M. Klutznick Professorial Chair of Developmental Biology in 2003. From 2000 to 2004, she served as President of the Israel Endocrine Society. Since 2015 she is a Professor Emeritus of the Weizmann Institute and presently serves as the Head of the Institutional Review Board. The scientific interest of Prof. Nava Dekel is directed at female reproduction and her studies are published in over 150 peer-reviewed articles, book chapters and conference proceedings.
Abstract
Vasorin: A Newly Identified Regulator of Ovarian Folliculogenesis and Ovulation
Progression through ovarian folliculogenesis is regulated by members of the TGFβ superfamily. Vasorin (Vasn) is a newly identified negative regulator of TGFβ signaling, whose possible involvement in ovarian physiology has never been studied. Our studies demonstrated for the first time that Vasn is expressed in the ovary by the somatic cells of follicles, and that its expression is upregulated by LH. We established a conditional knock out (cKO) mouse model, in which Vasn is deleted specifically in the granulosa cells of growing follicles, and showed that upon hormonal stimulation of these mice, ovulation size is almost two-fold higher. This enhanced ovulatory response is associated with over activation of the TGFβ signaling pathway and a lower number of atretic antral follicles. We observed that the number of primordial and primary follicles in pre-pubertal cKO mice ovaries is reduced, suggesting that production of Vasn by growing follicles protects the ovarian reserve. Finally, analysis of a systemic KO mouse model revealed that the ovarian reserve is almost 2.5-fold higher, implying that Vasn may also have a role during primordial follicle formation. Overall, our findings reveal that Vasn is a new regulator that controls several key ovarian functions, including the maintenance of the ovarian reserve, folliculogenesis and ovulation.