developmental embryology

To observe developmental changes in the ovarian tissue structure and distribution characteristics of oestrogen receptors (ERs) in the ovaries of Huanghuai goats at different ages, we selected healthy Huanghuai goats ewes and divided them into five groups (i.e. 3-, 30-, 60-, 90- and 120-day-old groups), with 10 animals in each group. The serum was separated after blood collection through the jugular vein, and the contents of oestrogen (E) and progesterone (P) in the serum of Huanghuai goats at each age were determined...

STUDY QUESTION: How do transcriptomics vary in haploid human androgenote embryos at single cell level in the first four cell cycles of embryo development? SUMMARY ANSWER: Gene expression peaks at the fourth cell cycle, however some androcytes exhibit unique transcriptional behaviors. WHAT IS KNOWN ALREADY: The developmental potential of an embryo is determined by the competence of the oocyte and the sperm. However, studies of the contribution of the paternal genome using pure haploid androgenotes are very scarce...

Dmrt (doublesex and mab-3 related transcription factor) is a protein family of transcription factors implicated in sexual regulation. Dmrt proteins are widely conserved and known for their involvement in sex determination and differentiation across species, from invertebrates to humans. In this study, we identified a novel gene with a DM (doublesex/Mab-3)-domain gene in the river prawn, Macrobrachium nipponense, which we named MniDmrt1B due to its similarities and close phylogenetic relationship with Dmrt1B in Macrobrachium rosenbergii...

Neural activity influences every aspect of nervous system development. In olfactory systems, sensory neurons expressing the same odorant receptor project their axons to stereotypically positioned glomeruli, forming a spatial map of odorant receptors in the olfactory bulb. As individual odors activate unique combinations of glomeruli, this map forms the basis for encoding olfactory information. The establishment of this stereotypical olfactory map requires coordinated regulation of axon guidance molecules instructed by spontaneous activity...

STUDY QUESTION: Can the addition of late embryogenesis-abundant (LEA) proteins as a cryoprotective agent during the vitrification cryopreservation of in vitro matured oocytes enhance their developmental potential after fertilization? SUMMARY ANSWER: LEA proteins improve the developmental potential of human in vitro matured oocytes following cryopreservation, mostly by downregulating FOS genes, reducing oxidative stress, and inhibiting the formation of ice crystals...

The megasporangium serves as a model system for understanding the concept of individual cell identity, and cell-to-cell communication in angiosperms. As development of the ovule progresses, three distinct layers, the epidermal (L1), the subepidermal or the hypodermal (L2) and the innermost layers (L3) are formed along the MMC (megaspore mother cell). The MMC, which is the primary female germline cell, is initiated as a single subepidermal cell amongst several somatic cells. MMC development is governed by various regulatory pathways involving intercellular signaling, small RNAs and DNA methylation...

Keratin 17 (K17) is thought to be a candidate target gene for regulation by Lymphoid Enhancer Factor-1 (Lef-1) . K17 is a marker that distinguishes junctional epithelium (JE) from epithelial rests of Malassez (ERM). However, the relationship of Lef-1 to K17 is not clear in this context. Moreover, the expression of other keratins such as K5, K6, K7 and K16 is not reported. Therefore, the aim of our study was to assay the expression of K5, K6, K7, K14, K16, K17 and Lef-1 in postnatal developing teeth, and clarify the corresponding immunophenotypes of the JE and ERM...

In vertebrate development, ectoderm is specified into neural plate (NP), neural plate border (NPB), and epidermis. Although such patterning is thought to be achieved by molecular concentration gradients, it has been revealed, mainly by in vitro analysis, that mechanical force can regulate cell specification. During in vivo patterning, cells deform and migrate, and this applies force to surrounding tissues, shaping the embryo. However, the role of mechanical force for cell specification in vivo is largely unknown...

Tooth formation is a process tightly regulated by reciprocal interactions between epithelial and mesenchymal tissues. These epithelial-mesenchyme interactions regulate the expression of target genes via transcription factors. Among the regulatory elements governing this process, Epiprofin/Sp6 is a zinc finger transcription factor which is expressed in the embryonic dental epithelium and in differentiating pre-odontoblasts. Epiprofin knockout ( Epfn -/-) mice present severe dental abnormalities, such as supernumerary teeth and enamel hypoplasia...

During development of the nervous system, neurons connect to one another in a precisely organized manner. Sensory systems provide a good example of this organization, whereby the composition of the outside world is represented in the brain by neuronal maps. Establishing correct patterns of neural circuitry is crucial, as inaccurate map formation can lead to severe disruptions in sensory processing. In rodents, olfactory stimuli modulate a wide variety of behaviors essential for survival. The formation of the olfactory glomerular map is dependent on molecular cues that guide olfactory receptor neuron axons to broad regions of the olfactory bulb and on cell adhesion molecules that promote axonal sorting into specific synaptic units in this structure...

Sensory signals detected by olfactory sensory organs are critical regulators of animal behavior. An accessory olfactory organ, the vomeronasal organ, detects cues from other animals and plays a pivotal role in intra- and inter-species interactions in mice. However, how ethologically relevant cues control mouse behavior through approximately 350 vomeronasal sensory receptor proteins largely remains elusive. The type 2 vomeronasal receptor-A4 (V2R-A4) subfamily members have been repeatedly detected from vomeronasal sensory neurons responsive to predator cues, suggesting a potential role of this receptor subfamily as a sensor for predators...

Mesenchymal stem cells (MSCs) derived from fetal membranes (FMs) have the potential to exhibit immunosuppression, improve blood flow, and increase capillary density during transplantation. In the field of medicine, opening up new avenues for disease treatment. Chicken embryo chorioallantoic membrane (CAM), as an important component of avian species FM structure, has become a stable tissue engineering material in vivo angiogenesis, drug delivery, and toxicology studies. Although it has been confirmed that chorionic mesenchymal stem cells (Ch-MSCs) can be isolated from the outer chorionic layer of FM, little is known about the biological characteristics of MSCs derived from chorionic mesodermal matrix of chicken embryos...

CLINICAL ISSUE: Congenital anomalies of the urogenital tract are common, whereas isolated developmental disorders of the genital organs are rare and varied. The type and timing of imaging to characterize these developmental disorders and the planning of any treatment are the subject of discussion. The aim of this article is to provide a brief overview of embryology, diagnostic procedures, and examples of findings. STANDARD RADIOLOGICAL METHODS: The primary procedure for imaging the genitals is sonography, which must be performed with appropriate empathy...

Adhesion of muscle stem cells to their niche provides stable anchorage, and biochemical and biomechanical signals required for quiescence. In their work, Robert Krauss and colleagues reveal the role of catenin/cadherin-based adhesion interactions in maintaining niche localization. To find out more about their work, we spoke to the first author, Margaret Hung, and the corresponding author, Robert Krauss, Professor in Cell, Developmental and Regenerative Biology at the Icahn School of Medicine, Mount Sinai.

The mammalian sense of smell relies upon a vast array of receptor proteins to detect odorant compounds present in the environment. The proper deployment of these receptor proteins in olfactory sensory neurons is orchestrated by a suite of epigenetic processes that remodel the olfactory genes in differentiating neuronal progenitors. The goal of this review is to elucidate the central role of gene regulatory processes acting in neuronal progenitors of olfactory sensory neurons that lead to a singular expression of an odorant receptor in mature olfactory sensory neurons...

No abstract text is available yet for this article.

Adult neurogenesis has fascinated the field of neuroscience for decades given the prospects of harnessing mechanisms that facilitate the rewiring and/or replacement of adult brain tissue. The subgranular zone of the hippocampus and the subventricular zone of the lateral ventricle are the two main areas in the brain that exhibit ongoing neurogenesis. Of these, adult-born neurons within the olfactory bulb have proven to be a powerful model for studying circuit plasticity, providing a broad and accessible avenue into neuron development, migration, and continued circuit integration within adult brain tissue...

Reversible transitions between epithelial and mesenchymal cell states are a crucial form of epithelial plasticity for development and disease progression. Recent experimental data and mechanistic models showed multiple intermediate epithelial-mesenchymal transition (EMT) states as well as trajectories of EMT underpinned by complex gene regulatory networks. In this review, we summarize recent progress in quantifying EMT and characterizing EMT paths with computational methods and quantitative experiments including omics-level measurements...

BACKGROUND: Neuronal lamination is a hallmark of the mammalian central nervous system (CNS) and underlies connectivity and function. Initial formation of this tissue architecture involves the integration of various signaling pathways that regulate the differentiation and migration of neural progenitor cells. RESULTS: Here, we demonstrate that mTORC1 mediates critical roles during neuronal lamination using the mouse retina as a model system. Down-regulation of mTORC1-signaling in retinal progenitor cells by conditional deletion of Rptor led to decreases in proliferation and increased apoptosis during embryogenesis...

STUDY QUESTION: How does a natural proliferative phase (NPP) strategy for frozen embryo transfer (FET) compare with the conventional artificial (AC) and natural (NC) endometrial preparation protocols in terms of live birth rates (LBR)? SUMMARY ANSWER: This study supports the hypothesis that, just as for NC, NPP-FET may be a superior alternative to AC in terms of LBR. WHAT IS KNOWN ALREADY: Although FETs are increasing worldwide, the optimal FET protocol is still largely controversial...