Search results for "BLAST"
showing 10 items of 2136 documents
Nickel, lead, and cadmium induce differential cellular responses in sea urchin embryos by activating the synthesis of different HSP70s.
2004
Treatment with heavy metals, such as nickel, lead or cadmium, elicits different cellular stress responses according to the metal used and the length of treatment. In Paracentrotus lividus embryos the inducible forms of HSP70 (HSP70/72) are different in molecular mass from the constitutively expressed HSP75, and they can be used as markers of cellular stress. Even a short treatment with each metal induces the synthesis of HSP70/72 which remain stable for at least 20 h and differ little in their isoelectric points. Continuous treatment from fertilization with nickel or lead produces late irregular pluteus embryos, with peak HSP70/72 synthesis at blastula followed by the arrest of synthesis by…
Evidence for differential and redundant function of the Sox genes Dichaete and SoxN during CNS development in Drosophila.
2002
Group B Sox-domain proteins encompass a class of conserved DNA-binding proteins expressed from the earliest stages of metazoan CNS development. In all higher organisms studied to date, related Group B Sox proteins are co-expressed in the developing CNS; in vertebrates there are three (Sox1, Sox2 and Sox3) and in Drosophila there are two (SoxNeuro and Dichaete). It has been suggested there may be a degree of functional redundancy in Sox function during CNS development. We describe the CNS phenotype of a null mutation in the Drosophila SoxNeuro gene and provide the first direct evidence for both redundant and differential Sox function during CNS development in Drosophila. In the lateral neuro…
Primary culture of single ectodermal precursors of Drosophila reveals a dorsoventral prepattern of intrinsic neurogenic and epidermogenic capabilitie…
1992
ABSTRACT We have analyzed the development in vitro of individual precursor cells from the presumptive truncal segmental ectoderm of the Drosophila embryo to study the intrinsic component in the determination of cell fate. For each cultured cell, the original position within as well as the developmental stage of the donor embryo were known. Cells removed from the ventral neurogenic region develop neural clones. Cells from the dorsal ectoderm and from the dorsalmost part of the ventral neurogenic ectoderm develop epidermal clones. These two classes of clones differ with respect to their division pattern, adhesiveness, cell morphologies and the expression of cell-specific markers. Mixed neural…
Molecular markers for identified neuroblasts in the developing brain of Drosophila.
2003
The Drosophila brain develops from the procephalic neurogenic region of the ectoderm. About 100 neural precursor cells (neuroblasts) delaminate from this region on either side in a reproducible spatiotemporal pattern. We provide neuroblast maps from different stages of the early embryo (stages 9, 10 and 11, when the entire population of neuroblasts has formed), in which about 40 molecular markers representing the expression patterns of 34 different genes are linked to individual neuroblasts. In particular, we present a detailed description of the spatiotemporal patterns of expression in the procephalic neuroectoderm and in the neuroblast layer of the gap genes empty spiracles, hunchback, hu…
The pattern of neuroblast formation, mitotic domains and proneural gene expression during early brain development in Drosophila.
2003
In the Drosophila embryo, studies on CNS development have so far mainly focused on the relatively simply structured ventral nerve cord. In the trunk, proneural genes become expressed in small cell clusters at specific positions of the ventral neuroectoderm. A lateral inhibition process mediated by the neurogenic genes ensures that only one cell within each proneural cluster delaminates as a neural stem cell (neuroblast). Thus, a fixed number of neuroblasts is formed, according to a stereotypical spatiotemporal and segmentally repeated pattern, each subsequently generating a specific cell lineage. Owing to higher complexity and hidden segmental organisation, the mechanisms underlying the dev…
Nonfluorescent RNA In Situ Hybridization Combined with Antibody Staining to Visualize Multiple Gene Expression Patterns in the Embryonic Brain of Dro…
2013
In Drosophila, the brain arises from about 100 neural stem cells (called neuroblasts) per hemisphere which originate from the neuroectoderm. Products of developmental control genes are expressed in spatially restricted domains in the neuroectoderm and provide positional cues that determine the formation and identity of neuroblasts. Here, we present a protocol for nonfluorescent double in situ hybridization combined with antibody staining which allows the simultaneous representation of gene expression patterns in Drosophila embryos in up to three different colors. Such visible multiple stainings are especially useful to analyze the expression and regulatory interactions of developmental cont…
Cellular Composition and Organization of the Subventricular Zone and Rostral Migratory Stream in the Adult and Neonatal Common Marmoset Brain
2011
The adult subventricular zone (SVZ) of the lateral ventricle contains neural stem cells. In rodents, these cells generate neuroblasts that migrate as chains toward the olfactory bulb along the rostral migratory stream (RMS). The neural-stem-cell niche at the ventricular wall is conserved in various animal species, including primates. However, it is unclear how the SVZ and RMS organization in nonhuman primates relates to that of rodents and humans. Here we studied the SVZ and RMS of the adult and neonatal common marmoset (Callithrix jacchus), a New World primate used widely in neuroscience, by electron microscopy, and immunohistochemical detection of cell-type-specific markers. The marmoset …
Histones and non-histone proteins during sea urchin development
1979
Abstract Chromatin from blastulae and plutei of Paracentrotus lividus was fractionated through a hydroxyapatite column. The ratio of histones versus non-histone proteins decreases from blastula to pluteus stage.
Beneficial Effect of Two Culture Systems with Small Groups of Embryos on the Development and Quality of In Vitro-Produced Bovine Embryos
2014
Summary Currently, in vitro-produced embryos derived by ovum pick up (OPU) and in vitro fertilization (IVF) technologies represent approximately one-third of the embryos worldwide in cattle. Nevertheless, the culture of small groups of embryos from an individual egg donor is an issue that OPU-IVF laboratories have to face. In this work, we tested whether the development and quality of the preimplantation embryos in vitro cultured in low numbers (five embryos) could be improved by the addition of epidermal growth factor, insulin, transferrin and selenium (EGF-ITS) or by the WOW system. With this aim, immature oocytes recovered from slaughtered heifers were in vitro matured and in vitro ferti…
Deep learning enables robust assessment and selection of human blastocysts after in vitro fertilization
2019
AbstractVisual morphology assessment is routinely used for evaluating of embryo quality and selecting human blastocysts for transfer after in vitro fertilization (IVF). However, the assessment produces different results between embryologists and as a result, the success rate of IVF remains low. To overcome uncertainties in embryo quality, multiple embryos are often implanted resulting in undesired multiple pregnancies and complications. Unlike in other imaging fields, human embryology and IVF have not yet leveraged artificial intelligence (AI) for unbiased, automated embryo assessment. We postulated that an AI approach trained on thousands of embryos can reliably predict embryo quality with…