Melanoma is a very aggressive tumor originating from neural-crest derived melanocytes. The transformation of normal melanocytes into melanoma cells is a multistep process. It is crucial to elucidate the molecular and cellular mechanisms of melanocyte development (specially the molecular network that controls the induction of neural crest) and transformation, to improve the prevention, early dia...

Early in the development of many animals, before transcription begins, any change in the pattern of protein synthesis is attributed to a change in the translational activity or stability of mRNA in the egg and early embryo. As a result, translational control is critical for a variety of developmental decisions, including oocyte maturation and initiation of preimplantation development. In this s...

Development of the early embryo is thought to be mainly driven by maternal gene products and post-transcriptional gene regulation. Here, we used metabolic labeling to show that RNA can be transferred by sperm into the oocyte upon fertilization. To identify genes with paternal expression in the embryo, we performed crosses of males and females from divergent Caenorhabditis elegans strains. RNA s...

During early stages of Drosophila development the heat-shock response cannot be induced. It is reasoned that the adverse effects on cell cycle and cell growth brought about by Hsp70 induction must outweigh the beneficial aspects of Hsp70 induction in the early embryo. Although the Drosophila heat shock transcription factor (dHSF) is abundant in the early embryo it does not enter the nucleus in ...

The mouse embryo generates multiple cell lineages, as well as its future body axes in the early phase of its development. The early cell fate decisions lead to the generation of three lineages in the pre-implantation embryo: the epiblast, the primitive endoderm and the trophectoderm. Shortly after implantation, the anterior-posterior axis is firmly established. Recent studies have provided a be...

Time-of-flight secondary ion mass spectrometry (ToF-SIMS) imaging has been used for the direct analysis of single intact Xenopus laevis embryo surfaces, locating multiple lipids during fertilization and the early embryo development stages with subcellular lateral resolution (∼4 μm). The method avoids the complicated sample preparation for lipid analysis of the embryos, which requires selective ...

Vasa is a DEAD-box RNA helicase that functions in translational regulation of specific mRNAs. In many animals it is essential for germ line development and may have a more general stem cell role. Here we identify vasa in two sea urchin species and analyze the regulation of its expression. We find that vasa protein accumulates in only a subset of cells containing vasa mRNA. In contrast to vasa m...

The preimplantation development of the mammalian embryo encompasses a series of critical events: the transition from oocyte to embryo, the first cell divisions, the establishment of cellular contacts, the first lineage differentiation-all the first subtle steps toward a future body plan. Here, we use microarrays to explore gene activity during preimplantation development. We reveal robust and d...

Recognition of early determinants of disease onset has sparked an interest in paternally transmitted factors and their impact on the developing embryo. Acrylamide (AA), a widely distributed xenobiotic compound, is converted to its active metabolite glycidamide (GA) by the CYP2E1 enzyme. Based on its capacity to induce dominant lethal mutations, we hypothesized that paternal GA exposure would ha...