Gene-distal enhancers are critical for tissue-specific gene expression, but their genomic determinants within a specific lineage at different stages of development are unknown. Here we profile chromatin state maps, transcription factor occupancy, and gene expression profiles during human erythroid development at fetal and adult stages. Comparative analyses of human erythropoiesis identify devel...

cryopreservation and sexing of embryos are integrated into commercial embryo transfer technologies. to improve the effectiveness of vitrification of in vitro produced buffalo embryos, two experiments were conducted. the first evaluated the effect of exposure time (2 and 3 min) and developmental stage (morula and blastocysts) on the viability and development of vitrified buffalo embryos. morphol...

Exercises that employ dynamic living material have proved highly successful at generating interest in science among young students. Developing embryos and larvae are especially well suited for such endeavors, for they can be handled without expensive or elaborate equipment, and their changing nature engages students. Using amphibian embryos, which are relatively large and exhibit profound, easi...

Biologists have long sought a means by which to quantify similarities and differences in embryonic development across species. Here we present a quantitative approach for predicting the timing of developmental events based on principles of allometry and biochemical kinetics. Data from diverse oviparous species support model predictions that most variation in the time required to reach one early...

The mammalian -globin loci each contain a family of developmentally expressed genes, and a far upstream regulatory element, the locus control region (LCR). In adult murine erythroid cells, the LCR and the transcribed -globin genes exist within domains of histone acetylation and RNA polymerase II (pol II) is associated with them. In contrast, the silent embryonic genes lie between these domains ...

Much is anticipated from the development and deployment of nanomaterials in biological organisms, but concerns remain regarding their biocompatibility and target specificity. Here we report our study of the transport, biocompatibility and toxicity of purified and stable silver nanoparticles (Ag NPs, 13.1 ± 2.5 nm in diameter) upon the specific developmental stages of zebrafish embryos using sin...

Apoptosis is an important event of the development of various organs. In this study, we used in situ terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) to visualize the temporal and spatial distribution of apoptosis in the developing medaka embryo, which is a useful model for developmental biology and genetics. Most of the apoptotic cells were distributed in the centr...

Early development is a dynamic process in higher organisms. A single fertilized egg gives rise to complex, standardized tissues, organs, and body plan. The genome sequence of several organisms has been determined, and the functions of individual genes associated with embryogenesis have been demonstrated in many studies (Stanford et al., 2001). The systematic analyses of the transcriptome and th...

Medulloblastoma is the most frequent malignant brain tumor of the posterior fossa in children and is considered an embryonal tumor. It has been suggested that medulloblastomas be categorized into 4 distinct molecular subgroups- WNT (DKK1), SHH (SFRP1), Group 3 (NPR3), or Group 4 (KCNA1)-since each subgroup is distinct and there is no overlap. The authors report on a 13-year-old boy with medullo...