Learn More
Embryonic stem cell (ESC) self-renewal efficiency is determined by the level of Nanog expression. However, the mechanisms by which Nanog functions remain unclear, and in particular, direct Nanog target genes are uncharacterized. Here we investigate ESCs expressing different Nanog levels and Nanog(-/-) cells with distinct functionally inducible Nanog(More)
One of the ultimate aims of systematics is the reconstruction of the tree of life. This is a huge undertaking that is inhibited by the existence of a computational limit to the inclusiveness of phylogenetic analyses. Supertree methods have been developed to overcome, or at least to go around this problem by combining smaller, partially overlapping(More)
A partial dinosaur skeleton from the Upper Triassic (Norian) sediments of South Africa is described and named Antetonitrus ingenipes. It provides the first informative look at a basal sauropod that was beginning to show adaptations towards graviportal quadrupedalism such as an elongated forelimb, a modified femoral architecture, a shortened metatarsus and a(More)
The extensive Early Jurassic continental strata of southern Africa have yielded an exceptional record of dinosaurs that includes scores of partial to complete skeletons of the sauropodomorph Massospondylus, ranging from embryos to large adults. In 1976 an incomplete egg clutch including in ovo embryos of this dinosaur, the oldest known example in the fossil(More)
Transcription factors, such as Oct4, are critical for establishing and maintaining pluripotent cell identity. Whereas the genomic locations of several pluripotency transcription factors have been reported, the spectrum of their interaction partners is underexplored. Here, we use an improved affinity protocol to purify Oct4-interacting proteins from mouse(More)
Embryonic stem (ES) cell self-renewal is regulated by transcription factors, including Oct4, Sox2, and Nanog. A number of additional transcriptional regulators of ES cell self-renewal have recently been identified, including the orphan nuclear receptor estrogen-related receptor beta (Esrrb). However, the mode of action of Esrrb in ES cells is unknown. Here,(More)
(2213 articles) evolution (296 articles) taxonomy and systematics (132 articles) palaeontology Articles on similar topics can be found in the following collections Email alerting service here right-hand corner of the article or click Receive free email alerts when new articles cite this article-sign up in the box at the top Aardonyx celestae gen. et sp.(More)
Apparently identical twin boys are both XX/XY and have two populations, A1 and B, of cells in their peripheral blood. Chimerism in somatic tissue outside the blood cells can be demonstrated in only one of the twins. From analysis of chromosomes and many gene markers the mechanism of origin of the unusual twins remains unclear.
The defining activity of the homeodomain protein Nanog is the ability to confer cytokine-independent self-renewal upon ES (embryonic stem) cells in which it is overexpressed. However, the biochemical basis by which Nanog achieves this function remains unknown. In the present study, we show that Nanog dimerizes through a functionally critical domain.(More)
Intrinsic regulators of the pluripotency of mouse ES (embryonic stem) cells include the homeodomain proteins Oct4 and the recently identified Nanog. When overexpressed, Nanog displays the unique attribute of robustly sustaining ES cell self-renewal in the absence of the otherwise requisite extracellular stimulation by LIF (leukaemia inhibitory factor) and(More)