scholarly journals Germ-layer commitment and axis formation in sea anemone embryonic cell aggregates

2018 ◽  
Vol 115 (8) ◽  
pp. 1813-1818 ◽  
Author(s):  
Anastasia Kirillova ◽  
Grigory Genikhovich ◽  
Ekaterina Pukhlyakova ◽  
Adrien Demilly ◽  
Yulia Kraus ◽  
...  

Robust morphogenetic events are pivotal for animal embryogenesis. However, comparison of the modes of development of different members of a phylum suggests that the spectrum of developmental trajectories accessible for a species might be far broader than can be concluded from the observation of normal development. Here, by using a combination of microsurgery and transgenic reporter gene expression, we show that, facing a new developmental context, the aggregates of dissociated embryonic cells of the sea anemone Nematostella vectensis take an alternative developmental trajectory. The self-organizing aggregates rely on Wnt signals produced by the cells of the original blastopore lip organizer to form body axes but employ morphogenetic events typical for normal development of distantly related cnidarians to re-establish the germ layers. The reaggregated cells show enormous plasticity including the capacity of the ectodermal cells to convert into endoderm. Our results suggest that new developmental trajectories may evolve relatively easily when highly plastic embryonic cells face new constraints.

Cancers ◽  
2020 ◽  
Vol 12 (4) ◽  
pp. 948 ◽  
Author(s):  
Henry E. Miller ◽  
Aparna Gorthi ◽  
Nicklas Bassani ◽  
Liesl A. Lawrence ◽  
Brian S. Iskra ◽  
...  

Ewing sarcoma is an aggressive pediatric cancer of enigmatic cellular origins typically resulting from a single translocation event t (11; 22) (q24; q12). The resulting fusion gene, EWSR1-FLI1, is toxic or unstable in most primary tissues. Consequently, attempts to model Ewing sarcomagenesis have proven unsuccessful thus far, highlighting the need to identify the cellular features which permit stable EWSR1-FLI1 expression. By re-analyzing publicly available RNA-Sequencing data with manifold learning techniques, we uncovered a group of Ewing-like tissues belonging to a developmental trajectory between pluripotent, neuroectodermal, and mesodermal cell states. Furthermore, we demonstrated that EWSR1-FLI1 expression levels control the activation of these developmental trajectories within Ewing sarcoma cells. Subsequent analysis and experimental validation demonstrated that the capability to resolve R-loops and mitigate replication stress are probable prerequisites for stable EWSR1-FLI1 expression in primary tissues. Taken together, our results demonstrate how EWSR1-FLI1 hijacks developmental gene programs and advances our understanding of Ewing sarcomagenesis.


2020 ◽  
Author(s):  
Bruno Facon

The aim was to investigate whether a progressive dissociation between the cognitive level and syntax comprehension occurs during the development of persons with intellectual disabilities (ID). Two cross-sectional developmental trajectory analyses were successively conducted. Study 1 comprised 615 typically developing participants and 615 participants with ID. Their total scores on a syntax comprehension test were regressed on a nonverbal cognitive measure and the slopes of the two groups’ regression lines were compared. In Study 2, logistic regression curves of the two groups for each of the 92 test items were compared. Results showed only negligible between-groups differences of developmental trajectories, whatever the level of analysis. The idea of a progressive dissociation between cognitive level and receptive syntactic skills of people with ID is not confirmed. However, a syntax test evaluating more complex sentences than those used in this study might show such a dissociation.


2013 ◽  
Vol 8 (5) ◽  
pp. 924-934 ◽  
Author(s):  
Michael J Layden ◽  
Eric Röttinger ◽  
Francis S Wolenski ◽  
Thomas D Gilmore ◽  
Mark Q Martindale

2010 ◽  
Vol 15 (4) ◽  
pp. 238-244 ◽  
Author(s):  
Bruce D Dick ◽  
Rebecca Pillai Riddell

Cognitive function is a critical factor related to a child’s overall developmental trajectory. There is increasing evidence that chronic pain disrupts cognitive function in adults. Little is known about the nature or impact of cognitive disruption in children and adolescents with chronic pain. The present review examines the current literature related to cognitive function in children and adolescents with chronic pain, implications of these findings and future research directions. Nine studies on this topic were found, with a relatively recent increase in publications related to school attendance and subjective studies of school performance. The studies that were found on this topic suggested that chronic pain affects cognitive function in children but the scope of these effects on children’s function and developmental trajectories is not yet clear. While methodological issues surely make it difficult to study cognitive function in children with chronic pain, the potential gains from such research warrant a pursuit of such work. Much remains to be studied on this important topic.


2021 ◽  
Author(s):  
Shane C. Miller ◽  
Diana P Baumann ◽  
M. Shane Merryman

The starlet sea anemone (Nematostella vectensis) is an emerging model organism, and we have maintained a colony at the Stowers Institute since 2007. Nematostella are known as a simple sea anemone, related to other cnidarians such as jellyfish and corals. Native to estuarine environments across the Atlantic coast of North America, from Novia Scotia to Florida, they encounter a variety of environmental conditions (e.g., temperature, salinity). Acknowledging that husbandry conditions and environmental parameters can impact research results we provide information about the housing, nutrition, maintenance, and health for our colony of Nematostella. This information will be applicable to any Nematostella housed in the facility in 2021.


2014 ◽  
Vol 11 (1) ◽  
pp. 44 ◽  
Author(s):  
Stefan M Jahnel ◽  
Manfred Walzl ◽  
Ulrich Technau

2020 ◽  
Author(s):  
Xin Niu ◽  
Alexei Taylor ◽  
Russell T. Shinohara ◽  
John Kounios ◽  
Fengqing Zhang

AbstractBrain regions change in different ways and at different rates. This staggered developmental unfolding is determined by genetics and postnatal experience and is implicated in the progression of psychiatric and neurological disorders. Neuroimaging-based brain-age prediction has emerged as an important new approach for studying brain development. However, the unidimensional brain-age estimates provided by previous methods do not capture the divergent developmental trajectories of various brain structures. Here we propose and illustrate an analytic pipeline to compute an index of multidimensional brain-age that provides regional age predictions. First, using a database of 556 subjects that includes psychiatric and neurological patients as well as healthy controls we conducted robust regression to characterize the developmental trajectory of each MRI-based brain-imaging feature. We then utilized cluster analysis to identify subgroups of imaging features with a similar developmental trajectory. For each identified cluster, we obtained a brain-age prediction by applying machine-learning models with imaging features belonging to each cluster. Brain-age predictions from multiple clusters form a multidimensional brain-age index (MBAI). The MBAI is more sensitive to alterations in brain structures and captured distinct regional change patterns. In particular, the MBAI provided a more flexible analysis of brain age across brain regions that revealed changes in specific structures in psychiatric disorders that would otherwise have been combined in a unidimensional brain age prediction. More generally, brain-age prediction using a subset of homogeneous features circumvents the curse of dimensionality in neuroimaging data.


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