Epithelial invagination, a basic morphogenetic process reiterated throughout embryonic development, generates tubular structures such as the neural tube, or pit-like structures such as the optic cup. The 'purse-string' hypothesis, which proposes that circumferential bands of actin microfilaments at the apical end of epithelial cells constrict to yield a curved epithelial sheet, has been widely ...

In many animal embryos, a specific gene expression pattern is established along the animal-vegetal axis soon after zygotic transcription begins. In the embryo of the ascidian Ciona intestinalis, soon after the division that separates animal and vegetal hemispheres into distinct blastomeres, maternal Gata.a and β-catenin activate specific genes in the animal and vegetal blastomeres, respectively...

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

The Xenopus Cripto-1 protein is confined to the cells of the animal hemisphere during early embryogenesis where it regulates the formation of anterior structures. Cripto-1 protein accumulates only in animal cells because cripto-1 mRNA in cells of the vegetal hemisphere is translationally repressed. Here, we show that the RNA binding protein, Bicaudal-C (Bic-C), functioned directly in this veget...

Sea urchin embryos initiate cell specifications at the 16-cell stage by forming the mesomeres, macromeres and micromeres according to the relative position of the cells in the animal-vegetal axis. The most vegetal cells, micromeres, autonomously differentiate into skeletons and induce the neighbouring macromere cells to become mesoendoderm in the β-catenin-dependent Wnt8 signalling pathway. Alt...

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...