Cerca Articoli

Loss of the Otx2-Binding Site in the Nanog Promoter Affects the Integrity of Embryonic Stem Cell Subtypes and Specification of Inner Cell Mass-Derived Epiblast

• Otx2 binds to the promoter/enhancer region of Oct4, Sox2, and Nanog in ESCs and EpiSCs • Otx2 binding to the Nanog promoter helps maintain the integrity of ESC compartments • Loss of this Otx2-binding site induces primed-like features in ESCs • Otx2 regulation of Nanog contributes to ICM differentiation of the epiblast Mouse embryonic stem cells (ESCs) and the inner cell mass (ICM)-derived epiblast exhibit naive pluripotency. ESC-derived epiblast stem cells (EpiSCs) and the postimplantation epiblast exhibit primed pluripotency. Although core pluripotency factors are well-characterized, additional regulators, including Otx2, recently have been shown to function during the transition from naive to primed pluripotency. Here we uncover a role for Otx2 in the control of the naive pluripotent state. We analyzed Otx2-binding activity in ESCs and EpiSCs and identified Nanog, Oct4, and Sox2 as direct targets. To unravel the Otx2 transcriptional network, we targeted the strongest Otx2-binding site in the Nanog promoter, finding that this site modulates the size of specific ESC-subtype compartments in cultured cells and promotes Nanog expression in vivo, predisposing ICM differentiation to epiblast. Otx2-mediated Nanog regulation thus contributes to the integrity of the ESC state and cell lineage specification in preimplantation development.

NASA Orders Second Boeing Crew Mission to International Space Station

Engineers from NASA’s Langley Research Center in Hampton, Virginia, and Boeing dropped a full-scale test article of the company’s CST-100 Starliner into Langley’s 20-foot-deep Hydro Impact Basin. Although the spacecraft is designed to land on land, Boeing is testing the Starliner’s systems in water to ensure astronaut safety in the unlikely event of an emergency during launch or ascent. Testing allows engineers to understand the performance of the spacecraft when it hits the water, how it will right itself and how to handle rescue and recovery operations. The test is part of the qualification phase of testing and evaluation for the Starliner system to ensure it is ready to carry astronauts to and from the International Space Station.

Rhythms del Mundo - Sting

Due to overwhelming fan demand, 2nd and FINAL Chicago Appearance Added at Wrigley Field on Friday, July 6, 2007... About RDM - Kenny Young's story so far...