Normal pattern formation during embryonic development requires the regulation of cellular competence to respond to inductive signals. In the Xenopus blastula, vegetal cells release mesoderm-inducing factors but themselves become endoderm, suggesting that vegetal cells may be prevented from expressing mesodermal genes in response to the signals that they secrete. We show here that addition of lo...

In leech embryos, segmental ectoderm and mesoderm are produced by a pair of sister cells located near the animal and vegetal poles, respectively. We have investigated the mechanism that localizes ectodermal and mesodermal fates along the animal-vegetal axis. The results of cleavage arrest and cell ablation experiments suggest that the full range of normal cell interactions are not required for ...

The maternal dorsal determinants required for the specification of the dorsal territories of Xenopus early gastrulae are located at the vegetal pole of unfertilised eggs and are moved towards the prospective dorsal region of the fertilised egg during cortical rotation. While the molecular identity of the determinants is unknown, there are dorsal factors in the vegetal cortical cytoplasm (VCC). ...

Esporotricosis fija con cuerpo asteroide junto al fragmento vegetal A fixed sporotrichosis with an asteroid body next to a vegetal fragment

1 Departamento de Biología Vegetal, Facultad de Ciencias, Universidad de Córdoba, Avda, San Alberto Magno, s/n, 14004-Córdoba, Spain. 2 Departamento de Biología Vegetal, Facultad de Ciencias, Universidad de Granada, 18001-Granada, Spain. 3 Unidad de Botánica, Facultad de Ciencias, Universidad Autónoma de Barcelona, 08193-Bellaterra, Barcelona, Spain. 4 Departamento de Biología Vegetal y Ciencia...

• The bell-pepper aroma typical of Cabernet Sauvignon and Sauvignon blanc has been correlated with the corresponding concentration of isobutyl-methoxypyrazine (IBMP). However, the term “vegetal” can include aromas other than bell-pepper. For example, many sulfur-containing compounds can elicit vegetal notes (e.g. asparagus, cooked corn, boxwood, rubber), and so can the norisoprenoid class of co...

Muscle gene expression is known to be induced in animal pole cells of a Xenopus blastula after 2-3 h of close contact with vegetal pole cells. We tested whether this induction requires functional gap junctions between vegetal and animal portions of an animal-vegetal conjugate. Muscle gene transcription was assayed with a muscle-specific actin gene probe and the presence or absence of communicat...

The specifications of cell types and germ-layers that arise from the vegetal plate of the sea urchin embryo are thought to be regulated by cell-cell interactions, the molecular basis of which are unknown. The Notch intercellular signaling pathway mediates the specification of numerous cell fates in both invertebrate and vertebrate development. To gain insights into mechanisms underlying the div...

We have used whole-mount immunofluorescence microscopy of late-stage Xenopus laevis oocytes and early embryos to examine the organization of their cortical cytokeratin systems. In both mature oocytes and early embryos, there is a distinct animal-vegetal polarity in cytokeratin organization. In mature (stage-VI) oocytes, the cytokeratin filaments of the vegetal region form a unique, almost geode...