.... In the present study, we comprehensively identified genes expressed specifically in ascidian muscle cells, and found that all of them are under control of a positive regulatory loop of Tbx6-r.b and Mrf , the core circuit identified previously. We also found that several transcription factors under control...

...Izumi Oda-Ishii; Deli Yu; Yutaka Satou ABSTRACT Zic-r.a, a maternal transcription factor, specifies posterior fate in ascidian embryos. However, its direct target, Tbx6-r.b , does not contain typical Zic-r.a-binding sites in its regulatory region. Using an in vitro selection assay, we found...

... regulatory factors, Zic-r.b, Tbx6-r.b and Mrf, and elucidate the mechanism by which these factors activate muscle structural genes. We reveal a cross-regulatory circuit among these regulatory factors, which maintains the expression of Tbx6-r.b and Mrf during gastrulation. Although these two factors...

... is ill defined. Here, we show that, unlike the myogenic trunk paraxial mesoderm, head mesoderm development is independent of the T/Tbx6 network in mouse. We reveal that, in contrast to Wnt and FGF-driven trunk mesoderm, dual inhibition of Wnt/β-catenin and Nodal specifies head mesoderm. Remarkably...

.... The current model for the mechanism controlling NMP deployment invokes Tbx6, a T-box factor, to drive mesoderm differentiation of NMPs. Here, we identify a new population of Tbx6 + cells in a subdomain of the NMP niche in mouse embryos. Based on co-expression of a progenitor marker, Sox2, we identify...

... analyses, we have found a clear link between Mesp2 transcription and the periodic waves of Notch activity. We also find that Mesp2 transcription is spatially defined by Tbx6: Mesp2 transcription and Tbx6 protein initially share an identical anterior border in the PSM, but once translated, Mesp2 protein...

... somites have dramatic effects on these tissues, including fusions of the ribs and vertebrae. The T-box transcription factor, Tbx6, is expressed in the paraxial mesoderm but is downregulated as somites develop. It is essential for the formation of posterior somites, which are replaced with ectopic neural...

... and rehydrated in a methanol series. Brachyury, Cdx4, Fgf8, Hnf3b, Hoxd11, Tbx6 and Wnt3a probes were kindly provided by Drs B. Herrmann, J. Deschamps, G. Martin, S.-L. Ang,D. Duboule, V. Papaioannou and A. McMahon, respectively. Whole-mount in situ hybridization was performed according to Wilkinson...

...-mail: [email protected] ) © 1999 by Company of Biologists 1999 T-box gene Notochord Somite Chordoneural hinge Motor neuron Overexpression Dominant-negative myoD shh ntl flh islet1 tbx6 spt Animal cap During gastrulation in vertebrate embryos, three definitive germ layers...

... by FGF signaling. Trunk and tail development are therefore dependent upon the complementary actions of two T-box genes, spadetail and no tail . We show that the regulatory hierarchy among spadetail, no tail and a third T-box gene, tbx6 , are substantially different during trunk and tail mesoderm...