Radial glia cells function as guide cells for neuronal migration and a source of neural progenitor cells, and play a crucial role for the development of the central nervous system. To date, several signals have been demonstrated to promote the formation of radial glia cells and Notch signaling is one such signal. However, the mechanism of the signaling hierarchy of radial glia developmental cascade promoted by Notch signaling still remains incomplete.
View Article and Find Full Text PDFThe pronephros is a transient embryonic kidney that is essential for the survival of aquatic larvae. It is also absolutely critical for adult kidney development, as the pronephric derivative the wolffian duct forms the ductal system of the adult kidney and also triggers the condensation of metanephric mesenchyme into the adult nephrons. While exploring Xenopus pronephric patterning, we observed that epidermally delivered hedgehog completely suppresses pronephric kidney tubule development but does not effect development of the pronephric glomus, the equivalent of the mammalian glomerulus or corpuscle.
View Article and Find Full Text PDFBackground: Research using the model system Xenopus laevis has provided critical insights into the mechanisms of early vertebrate development and cell biology. Large scale sequencing efforts have provided an increasingly important resource for researchers. To provide full advantage of the available sequence, we have analyzed 350,468 Xenopus laevis Expressed Sequence Tags (ESTs) both to identify full length protein encoding sequences and to develop a unique database system to support comparative approaches between X.
View Article and Find Full Text PDFPatterning of the pre-gastrula embryo and subsequent neural induction post-gastrulation are very complex and intricate processes of which little, until recently, has been understood. The earliest decision in neural development, the choice between epidermal or neural fates, is regulated by bone morphogenetic protein (BMP) signaling within the ectoderm. Inhibition of BMP signaling is sufficient for neural induction.
View Article and Find Full Text PDFThe earliest decision in vertebrate neural development is the acquisition of a neural identity by embryonic ectodermal cells. The default model for neural induction postulates that neural fate specification in the vertebrate embryo occurs by inhibition of epidermal inducing signals in the gastrula ectoderm. Bone morphogenetic proteins (BMPs) act as epidermal inducers, and all identified direct neural inducers block BMP signaling either intra- or extracellularly.
View Article and Find Full Text PDFBone homeostasis is maintained by the balanced action of bone-forming osteoblasts and bone-resorbing osteoclasts. Multinucleated, mature osteoclasts develop from hematopoietic stem cells via the monocyte-macrophage lineage, which also give rise to macrophages and dendritic cells. Despite their distinct physiologic roles in bone and the immune system, these cell types share many molecular and biochemical features.
View Article and Find Full Text PDFThe latent TGF-beta binding proteins (LTBP) are believed to control the availability of TGF-beta in the extracellular milieu. To gain insight into the potential roles of LTBP in early development, we isolated the Xenopus LTBP-1 (xLTBP-1) cDNA. The cDNA encodes a protein similar to the mammalian LTBP-1 in both size and domain structure.
View Article and Find Full Text PDFMammalian and Drosophila homologues of Baf57 have been previously isolated as being a subunit of SWI/SNF-like chromatin remodeling complexes. Here, we report the cloning and developmental expression of Xenopus Baf57. We isolated XBaf57 by using an expression cloning approach to identify novel modulators of Xenopus Smad7.
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