Expression and localization of ARTEMIN in the bovine uterus and embryos

Artemin a member of the glial cell line-derived neurotrophic factor (GDNF) family is present in mice and human preimplantation embryos, and reproductive tract, during early pregnancy promoting embryo development in vitro. The presence of artemin in cattle embryos and reproductive tract, however, is unknown. In the present work we identified for first time artemin in bovine uterine fluid (UF) (Western blot), endometrium (RT-PCR, Western blot and immunohistochemistry) and embryos (RT-PCR and immunohistochemistry) during early preimplantation development. In addition, GFRalpha3, a component of the artemin receptor was localized in blastocysts produced in vitro. Individually developing embryos released ARTEMIN in culture medium and triggered ARTEMIN mRNA down-regulation in epithelial cells from endometrial cell cultures. Our results suggest that ARTEMIN derived from early embryos and maternal reproductive tract may exert important roles during early development in cattle.