Ethanol-treated Lytechinus variegatus (sea urchin) embryos
Ontology highlight
ABSTRACT:
ORGANISM(S): Lytechinus variegatus
PROVIDER: GSE207100 | GEO | 2022/06/28
REPOSITORIES: GEO
Similar Datasets
Project description:Ethanol-treated Lytechinus variegatus (sea urchin) embryos
| PRJNA853740 | ENA
Project description:Using scRNA-seq coupled with computational approaches, we studied transcriptional changes in cell states of sea urchin embryos during development to the larval stage. Eighteen closely spaced time points were taken during the first 24 hours of development of Lytechinus variegatus (Lv). Developmental trajectories were constructed using Waddington-OT, a computational approach to "stitch" together developmental timepoints. Skeletogenic and primordial germ cell trajectories diverged early in cleavage. Ectodermal progenitors were distinct from other lineages by sixth cleavage, though a small percentage of ectoderm cells briefly co-expressed endoderm markers indicating an early ecto-endoderm cell state, likely in cells originating from the equatorial region of the egg. Endomesoderm cells originated at 6th cleavage also and this state persisted for more than two cleavages, then diverged into distinct endoderm and mesoderm fates asynchronously, with some cells retaining an intermediate specification status until gastrulation. 79 of 80 genes (99%) examined, and included in published developmental gene regulatory networks (dGRNs), are present in the Lv-scRNA-seq dataset, and expressed in the correct lineages in which the dGRN circuits operate.
2021-09-24 | GSE184538 | GEO
Project description:Sea urchins are emblematic marine animals with a rich fossil record and represent instrumental models for developmental biology. As echinoderms, sea urchins display several characteristics that set them apart from other deuterostomes such as their highly regulative embryonic development and their unique pentaradial adult body plan. To determine whether these characteristics are linked to particular genomic rearrangement or gene regulatory rewiring, we introduce a chromosome-scale genome assembly for sea urchin Paracentrotus lividus as well as extensive transcriptomic and epigenetic profiling during its embryonic development. We found that sea urchins show opposite modalities of genome evolution as compared to those of vertebrates: they retained ancestral chromosomal linkages that otherwise underwent mixing in vertebrates, while their intrachromosomal gene order has evolved much faster between sea urchin species that split 60 Myr ago than it did in vertebrates. We further assessed the conservation of the cis-regulatory program between sea urchins and chordates and identified conserved modules despite the developmental and body plan differences. We documented regulatory events underlying processes like zygotic genome activation and transition to larval stage in sea urchins. We also identified a burst of gene duplication in the echinoid lineage and showed that some of these expanded genes are involved in organismal novelties, such as Aristotle's lantern, tube feet, or in the specification of lineages through for instance the pmar1 and pop genes. Altogether, our results suggest that gene regulatory networks controlling development can be conserved despite extensive gene order rearrangement.
2023-02-09 | GSE202034 | GEO
Project description:Sea urchins lack proper eye organs but are photosensitive. In this study, we investigate an extraocular photoreceptor cell (PRC) system in developmental stages of the sea urchin Paracentrotus lividus.
2022-09-20 | GSE211842 | GEO
Project description:Sea urchins (echinoids) are common model organisms for research in developmental biology and for their transition from a bilateral larva into their post-metamorphic adult with pentaradial body symmetry. The adult also has a calcareous endoskeleton with a multimetameric pattern of continuously added elements, among them the namesake of this phylum, spines. Nearly all echinoids have both large primary spines, and an associated set of smaller secondary spines.We hypothesize that the secondary spines of the tropical variegated urchin species, Lytechinus variegatus, are morphologically and molecularly distinct structures from primary spines and not just small spines. To test this premise, we examined both spine types using light microscopy, micro-CT imaging, lectin labeling, transcriptomics, and fluorescent in situ hybridization (FISH). Our findings reveal basic similarities between the two types in mineral and cellular anatomy, but with clear differences in growth patterns, genes expressed, and in the location of gene expression within the two types of spines. In particular, secondary spines have non-overlapping, longitudinally concentrated growth bands that lead to a blunt and straight profile, and a distinct transcriptome involving the upregulation in many genes in comparison to the primary spines. Neural, ciliary, and extracellular matrix interacting factors are implicated in the differentially expressed gene (DEG) dataset, including two genes - ONECUT2 and an uncharacterized discoidin- and thrombospondin-containing protein - that show spine type- specific localizations in FISH, and may be of interest to ongoing work in urchin spine patterning.These results demonstrate that primary and secondary spines have overlapping but distinct molecular and biomineralized characteristics, suggesting unique developmental and regenerative mechanisms, and devotion to this spiny dermal phylum.
2024-05-15 | GSE267428 | GEO
Project description:Sea stars and sea urchins are model systems for interrogating the types of deep evolutionary changes that have restructured developmental gene regulatory networks (GRNs). While cis regulatory DNA evolution is likely the predominant mechanism of change, it was recently shown that Tbrain, a Tbox transcription factor protein, has evolved a changed preference for a low affinity, secondary binding motif, although the primary, high affinity motif is conserved. To date, however, no genome-wide comparisons have been performed in order to provide an unbiased assessment of the evolution of GRNs between these taxa; and no study has attempted to determine the interplay between transcription factor binding motif evolution and GRN topology. The study here measures genome-wide binding of Tbrain orthologs using ChIP-seq, and associates these with putative target genes to assess global function. Targets of both factors are enriched for other regulatory genes, although non-overlapping sets of functional enrichments in the two datasets suggest a much diverged function. The number of low affinity binding motifs are significantly depressed in sea urchins compared to sea star, but both motifs types are associated with genes from a range of functional categories. Only a small fraction (~10%) of genes are predicted to be orthologous targets. Collectively these data indicate that Tbr has evolved significantly different developmental roles in these echinoderms, and that the maintained and unique targets, and their associated binding motifs are dispersed throughout the hierarchy of the GRN, rather than being biased towards terminal process or discrete functional blocks suggesting extensive evolutionary tinkering.
2016-12-01 | GSE89862 | GEO
Project description:Marine bioadhesives have unmatched performances especially in wet environments, being valuable sources of inspiration for industrial and biomedical applications. In sea urchins specialized adhesive organs, called tube feet, mediate adhesion. These are composed by a disc, which produces adhesive and de-adhesive secretions for strong reversible attachment, and a motile stem. After detachment, the secreted adhesive remains bound to the substratum as a footprint. Previous studies showed that sea urchin adhesive is composed of proteins and sugars, but so far only one protein, Nectin, was shown to be over-expressed as a transcript in tube feet discs, suggesting its involvement in sea urchin adhesion. Here we use high-resolution quantitative mass-spectrometry technologies to profile Paracentrotus lividus tube feet differential proteome, comparing protein expression levels in its adhesive part (disc) versus the non-adhesive part (stem). This allowed us to identify 163 highly over-expressed disc proteins and propose the first molecular model of sea urchin reversible adhesion. The secreted adhesive proteome was also analyzed, whereby we found that 70% of its components fall within five protein groups, involved in adhesive exocytosis and protection against microbes. Our data also provides evidence that Nectin is not only highly expressed in tube feet discs but is a component of the adhesive itself, thus constituting the first report of a sea urchin tube foot adhesive protein. These results give us an unprecedented insight on the molecular mechanics underlying sea urchins reversible adhesion, opening new doors to develop new, wet-reliable, reversible, efficient, ecological biomimetic adhesives.
2016-03-21 | PXD003122 | Pride
Project description:Ocean acidification is recognized as one of the most pervasive anthropogenic impact on marine life. A variety of responses have been highlighted in different marine organisms ranging from physiology to gene and protein expression. However, most of these studies have been performed in laboratory exposing adults or developmental stages to CO2 enriched seawater. To what extend the information obtained from these in vitro experiments may be extrapolated to a natural environment is questionable. Here, we utilized the Castello volcanic CO2 vents at Ischia as natural laboratory to study the P. lividus population living at the low pH zone (pH~7.8) compared to those of sea urchins living at control sites. Wide-ranging analyses were performed in animals collected at the acidified site, including the monitoring of their position, the determination of the physico-chemical parameters of the coelomic fluid and an in depth characterization of coelomocytes regarding the number and type of cells, Hsp70 expression, redox status and protein expression through de-novo sequencing analyses. In addition, the respiration, nitrogen metabolism, and skeletal mineralogy of urchins from the vent were examined in comparison with those from control animals. Overall these analyses allowed to understand how the sea urchins can thrive in low pH/high CO2.
2022-02-28 | PXD009395 | Pride
Project description:Transcription factor SoxC is required for all neural development in purple sea urchin S. purpuratus embryos. To begin to develop a gene regulatory network for neural development, we used RNA-Seq to compare transcript populations in SoxC knockdown and control embryos.
2015-12-16 | GSE76067 | GEO
Project description:Evolutionary transitions enable the wide diversity in life histories of plants and animals. This is particularly germane in the development of the germline in which fitness is a direct readout of evolutionary change. Here, we focused on two distinct sea urchin species who shared a common ancestor 50 million years ago. Even though they both rely on inherited mechanisms to specify their germ line, the integration of stage-matched scRNA seq datasets from these two sea urchins revealed, amongst others, a broader expression of Nanos2 in Lytechinus variegatus (Lv) compared to Strongylocentrotus purpuratus (Sp). In Sp, Nanos2 mRNA expression is highly restricted to the PGCs by a lability element in its 3’UTR. This element is lacking in Lv Nanos2, explaining how this mRNA more broadly accumulates in the Lv embryos. We discovered that the Lv Nanos2 3’UTR instead leads to a germline specific translation of the protein. The results emphasize that regulatory mechanisms resulting in germline diversity rely less on transcriptional regulation and more on post-transcriptional and post-translational restrictions of key gene products, such as Nanos2.
2023-01-19 | GSE208709 | GEO