Template:2019 New References: Difference between revisions
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[[User:Z8600021|Mark Hill]] ([[User talk:Z8600021|talk]]) 12:23, 16 June 2019 (AEST) Added this new page to capture updated references added throughout the site in the "Some Recent Findings". Entries are listed alphabetically by topic page, note that not all new references may be added to this current list. (More? [[New]]) | [[User:Z8600021|Mark Hill]] ([[User talk:Z8600021|talk]]) 12:23, 16 June 2019 (AEST) Added this new page to capture updated references added throughout the site in the "Some Recent Findings". Entries are listed alphabetically by topic page, note that not all new references may be added to this current list. (More? [[New]]) | ||
{{BMP}} | |||
* '''BMP controls dorsoventral and neural patterning in indirect-developing hemichordates providing insight into a possible origin of chordates'''{{#pmid:31189599|PMID31189599}} "A defining feature of chordates is the unique presence of a dorsal hollow neural tube that forms by internalization of the ectodermal neural plate specified via inhibition of BMP signaling during gastrulation. While BMP controls dorsoventral (DV) patterning across diverse bilaterians, the BMP-active side is ventral in chordates and dorsal in many other bilaterians. How this phylum-specific DV inversion occurs and whether it is coupled to the emergence of the dorsal neural plate are unknown. Here we explore these questions by investigating an indirect-developing enteropneust from the hemichordate phylum, which together with echinoderms form a sister group of the chordates. We found that in the hemichordate larva, BMP signaling is required for DV patterning and is sufficient to repress neurogenesis. We also found that transient overactivation of BMP signaling during gastrulation concomitantly blocked mouth formation and centralized the nervous system to the ventral ectoderm in both hemichordate and sea urchin larvae. Moreover, this mouthless, neurogenic ventral ectoderm displayed a medial-to-lateral organization similar to that of the chordate neural plate. Thus, indirect-developing deuterostomes use BMP signaling in DV and neural patterning, and an elevated BMP level during gastrulation drives pronounced morphological changes reminiscent of a DV inversion. These findings provide a mechanistic basis to support the hypothesis that an inverse chordate body plan emerged from an indirect-developing ancestor by tinkering with BMP signaling." | |||
{{cerebellum}} | |||
* '''Fetal Growth Restriction Alters Cerebellar Development in Fetal and Neonatal {{Sheep}}'''{{#pmid:31191328|PMID31191328}} "Fetal growth restriction (FGR) complicates 5-10% of pregnancies and is associated with increased risks of perinatal morbidity and mortality. The development of cerebellar neuropathology in utero, in response to chronic fetal hypoxia, and over the period of high risk for preterm birth, has not been previously studied. ... FGR lambs demonstrated neuropathology within the cerebellum after birth, with a significant, ~18% decrease in the number of granule cell bodies (NeuN+ immunoreactivity) within the internal granular layer (IGL) and an ~80% reduction in neuronal extension and branching (MAP+ immunoreactivity) within the molecular layer (ML). Oxidative stress (8-OHdG+ immunoreactivity) was significantly higher in FGR lambs within the ML and the white matter (WM) compared to control lambs. The structural integrity of neurons was already aberrant in the FGR cerebellum at 115 d GA, and by 124 d GA, inflammatory cells (Iba-1+ immunoreactivity) were significantly upregulated and the blood-brain barrier (BBB) was compromised (Pearls, albumin, and GFAP+ immunoreactivity). We confirm that cerebellar injuries develop antenatally in FGR, and therefore, interventions to prevent long-term motor and coordination deficits should be implemented either antenatally or perinatally, thereby targeting neuroinflammatory and oxidative stress pathways." | |||
{{chemicals}} | {{chemicals}} | ||
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{{Hypothalamus}} | {{Hypothalamus}} | ||
* '''Development of the Basal Hypothalamus through Anisotropic Growth'''{{#pmid:31050853|PMID31050853}} "The adult hypothalamus is subdivided into distinct domains: pre-optic, anterior, tuberal and mammillary. Each domain harbours an array of neurons that act together to regulate homeostasis. The embryonic origins and development of hypothalamic neurons, however, remains enigmatic. Here we summarise recent studies in model organisms that challenge current views of hypothalamic development, which traditionally have attempted to map adult domains to correspondingly-located embryonic domains that expand isotropically. Instead, new studies indicate that hypothalamic neurons arise from progenitor cells that undergo anisotropic growth in different dimensions. Here we describe how a multipotent Shh/ Fgf10-expressing progenitor population gives rise to progenitors that grow anisotropically, expanding to a greater extent than other progenitors and giving rise to cells throughout the basal hypothalamus. Further, Shh/Fgf10+ive -derived progenitors grow sequentially in different directions from the multipotent Shh/ Fgf10 population: first, a subset displaced rostrally give rise to anterior-ventral/tuberal neuronal progenitors, then a subset displaced caudally give rise to mammillary neuronal progenitors; finally, a subset(s) displaced ventrally give rise to tuberal infundibular glial progenitors. As this occurs, stable populations of Shh+ive and Fgf10+ive progenitors form. We describe current understanding of the mechanisms that induce Shh/Fgf10+ive progenitors, and begin to direct their differentiation to anterior-ventral/tuberal neuronal progenitors, mammillary neuronal progenitors and tuberal infundibular progenitors. Together these studies suggest a new model for hypothalamic development that we term the Anisotropic growth model. We discuss the implications of the model for understanding the origins of adult hypothalamic neurons." | * '''Development of the Basal Hypothalamus through Anisotropic Growth'''{{#pmid:31050853|PMID31050853}} "The adult hypothalamus is subdivided into distinct domains: pre-optic, anterior, tuberal and mammillary. Each domain harbours an array of neurons that act together to regulate homeostasis. The embryonic origins and development of hypothalamic neurons, however, remains enigmatic. Here we summarise recent studies in model organisms that challenge current views of hypothalamic development, which traditionally have attempted to map adult domains to correspondingly-located embryonic domains that expand isotropically. Instead, new studies indicate that hypothalamic neurons arise from progenitor cells that undergo anisotropic growth in different dimensions. Here we describe how a multipotent Shh/ Fgf10-expressing progenitor population gives rise to progenitors that grow anisotropically, expanding to a greater extent than other progenitors and giving rise to cells throughout the basal hypothalamus. Further, Shh/Fgf10+ive -derived progenitors grow sequentially in different directions from the multipotent Shh/ Fgf10 population: first, a subset displaced rostrally give rise to anterior-ventral/tuberal neuronal progenitors, then a subset displaced caudally give rise to mammillary neuronal progenitors; finally, a subset(s) displaced ventrally give rise to tuberal infundibular glial progenitors. As this occurs, stable populations of Shh+ive and Fgf10+ive progenitors form. We describe current understanding of the mechanisms that induce Shh/Fgf10+ive progenitors, and begin to direct their differentiation to anterior-ventral/tuberal neuronal progenitors, mammillary neuronal progenitors and tuberal infundibular progenitors. Together these studies suggest a new model for hypothalamic development that we term the Anisotropic growth model. We discuss the implications of the model for understanding the origins of adult hypothalamic neurons." | ||
{{mouse}} | |||
* '''Molecular recording of mammalian embryogenesis'''{{#pmid:31086336|PMID31086336}} "Ontogeny describes the emergence of complex multicellular organisms from single totipotent cells. This field is particularly challenging in mammals, owing to the indeterminate relationship between self-renewal and differentiation, variation in progenitor field sizes, and internal gestation in these animals. Here we present a flexible, high-information, multi-channel molecular recorder with a single-cell readout and apply it as an evolving lineage tracer to assemble mouse cell-fate maps from fertilization through gastrulation. By combining lineage information with single-cell RNA sequencing profiles, we recapitulate canonical developmental relationships between different tissue types and reveal the nearly complete transcriptional convergence of endodermal cells of extra-embryonic and embryonic origins. Finally, we apply our cell-fate maps to estimate the number of embryonic progenitor cells and their degree of asymmetric partitioning during specification. Our approach enables massively parallel, high-resolution recording of lineage and other information in mammalian systems, which will facilitate the construction of a quantitative framework for understanding developmental processes." | |||
{{preterm birth}} | {{preterm birth}} | ||
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{{vein}} | {{vein}} | ||
* '''Venous Collateral Pathways in Superior Thoracic Inlet Obstruction: A Systematic Analysis of Anatomy, Embryology, and Resulting Patterns'''{{#pmid:31039029|PMID31039029}} "For this study, we reviewed 56 standard-of-care CT examinations over a timespan of 2 years from patients with superior thoracic inlet venous obstruction and identified eight thoracic collateral pathways for venous blood return to the right heart. We evaluated each pathway individually from an anatomic and a pathophysiologic perspective for a better understanding of how such pathways form and what patterns can be expected. ... Recognizing imaging findings associated with venous collateral pathways may prevent misdiagnosis or unnecessary follow-up examinations. Furthermore, knowledge of these collateral pathways and an understanding of the underlying cause can support interventional radiologists and vascular surgeons in planning interventional procedures and revascularization procedures." | * '''Venous Collateral Pathways in Superior Thoracic Inlet Obstruction: A Systematic Analysis of Anatomy, Embryology, and Resulting Patterns'''{{#pmid:31039029|PMID31039029}} "For this study, we reviewed 56 standard-of-care CT examinations over a timespan of 2 years from patients with superior thoracic inlet venous obstruction and identified eight thoracic collateral pathways for venous blood return to the right heart. We evaluated each pathway individually from an anatomic and a pathophysiologic perspective for a better understanding of how such pathways form and what patterns can be expected. ... Recognizing imaging findings associated with venous collateral pathways may prevent misdiagnosis or unnecessary follow-up examinations. Furthermore, knowledge of these collateral pathways and an understanding of the underlying cause can support interventional radiologists and vascular surgeons in planning interventional procedures and revascularization procedures." | ||
{{X inactivation}} | |||
* '''The bipartite TAD organization of the X-inactivation center ensures opposing developmental regulation of Tsix and Xist'''{{#pmid:31133748|PMID31133748}} "The mouse X-inactivation center (Xic) locus represents a powerful model for understanding the links between genome architecture and gene regulation, with the non-coding genes {{Xist}} and Tsix showing opposite developmental expression patterns while being organized as an overlapping sense/antisense unit. The Xic is organized into two topologically associating domains (TADs) but the role of this architecture in orchestrating cis-regulatory information remains elusive. To explore this, we generated genomic inversions that swap the Xist/Tsix transcriptional unit and place their promoters in each other's TAD. We found that this led to a switch in their expression dynamics: Xist became precociously and ectopically upregulated, both in male and female pluripotent cells, while Tsix expression aberrantly persisted during differentiation. The topological partitioning of the Xic is thus critical to ensure proper developmental timing of X inactivation. Our study illustrates how the genomic architecture of cis-regulatory landscapes can affect the regulation of mammalian developmental processes." | |||
{{zygote}} | |||
* '''Pleomorphic Adenoma Gene 1 Is Needed For Timely Zygotic Genome Activation and Early Embryo Development'''{{#pmid:31182756|PMID31182756}} "Pleomorphic adenoma gene 1 (PLAG1) is a transcription factor involved in cancer and growth. We discovered a de novo DNA motif containing a PLAG1 binding site in the promoters of genes activated during zygotic genome activation (ZGA) in human embryos. This motif was located within an Alu element in a region that was conserved in the murine B1 element. We show that maternally provided Plag1 is needed for timely mouse preimplantation embryo development. Heterozygous mouse embryos lacking maternal Plag1 showed disrupted regulation of 1,089 genes, spent significantly longer time in the 2-cell stage, and started expressing Plag1 ectopically from the paternal allele. The de novo PLAG1 motif was enriched in the promoters of the genes whose activation was delayed in the absence of Plag1. Further, these mouse genes showed a significant overlap with genes upregulated during human ZGA that also contain the motif. By gene ontology, the mouse and human ZGA genes with de novo PLAG1 motifs were involved in ribosome biogenesis and protein synthesis. Collectively, our data suggest that PLAG1 affects embryo development in mice and humans through a conserved DNA motif within Alu/B1 elements located in the promoters of a subset of ZGA genes." | |||
Revision as of 12:32, 27 June 2019
2019 New References |
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Mark Hill (talk) 12:23, 16 June 2019 (AEST) Added this new page to capture updated references added throughout the site in the "Some Recent Findings". Entries are listed alphabetically by topic page, note that not all new references may be added to this current list. (More? New)
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