Characterization of goat inner cell mass derived cells in double kinase inhibition condition.

The identification of small molecular inhibitors, which were reported to promote the derivation of mouse and human embryonic stem cells (ESCs), provides a potential strategy for the derivation of domesticated ungulate ESCs. In present study, goat inner cell mass (ICM) derived cells in the double inhibition (2i) condition, in which, mitogen-activated protein kinase kinase (MAP2K) and glycogen synthase kinase 3 (GSK3) were inhibited by PD0325901 and BIO respectively, were characterized. The results showed that goat ICM derived cells in 2i medium adding leukaemia inhibitor factor (LIF) possessed a mouse ES-like morphology. But these cells had much compromised proliferation capacity, resulting in difficulty in expansion. In 2i alone medium, goat ICM derived cells possessed primate ES-like morphology. These cells expressed pluripotent markers and could differentiate into derivatives of three germ layers in vitro. However, these cells could not be proliferated in long-term (persisted for 15 passages) because of spontaneously neural differentiation. Additionally, goat ICM derived cells could be inducing differentiated into neural lineage in vitro. Although goat ESCs could not be established in PD0325901 and BIO alone medium, this derivation condition provides a useful research system to find signaling molecular those regulate early embryonic development and pluripotency in goat.

NPR2 is involved in FSH-mediated mouse oocyte meiotic resumption.

BACKGROUND: Previous studies have reported that follicle-stimulating hormone (FSH) is often added to culture media to induce oocyte meiotic resumption and maturation and to improve subsequent embryonic development during in vitro maturation (IVM). However, the underlying mechanisms remain unclear. METHODS: Cumulus-oocyte complexes (COCs) were collected from ovaries 46-48 h after the female mice were intraperitoneally injected with 8 IU equine chorionic gonadotropin (eCG) and then the COCs were cultured in different medium. qRT-PCR analysis was used to assess mRNA expression of EGF-like factors and natriuretic peptide receptor 2 (NPR2). Western Blot analysis was used to assess phosphorylation of mitogen-activated protein kinase 3/1 (MAPK3/1). The oocytes were morphologically assessed for meiotic resumption. RESULTS: FSH stimulated the expression of EGF-like factors, the activation of MAPK3/1, a decrease in NPR2 mRNA and oocyte meiotic resumption. Moreover, the FSH-induced decrease in NPR2 and oocyte meiotic resumption occurred via the MAPK3/1 singling pathway, which was activated by the epidermal growth factor receptor (EGFR) pathway. CONCLUSIONS: NPR2 is involved in FSH-mediated oocyte meiotic resumption, and this process is associated with the EGFR and MAPK3/1 signaling pathways.