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.
Project description:We identified cis-regulatory elements based on their dynamic chromatin accessibility during the gastrula-larva stages of sea urchin and sea star and studied their evolution in these echinoderm species
Project description:Here we present LC-MS/MS proteomic datasets of Heliocidaris erythrogramma, Heliocidaris tuberculata, and Lytechinus variegatus eggs and larvae. We find dramatic proteomic differences likely associated with life history evolution and between developmental stages. This study provides a complimentary dataset to previous transcriptomic analyses of the same three sea urchin species.
Project description:The red sea urchin, Mesocentrotus franciscanus, is one the earth’s longest-lived animals, reported to live more than 100 years with indeterminate growth, life-long reproduction and no increase in mortality rate with age. To explore the idea that transcriptional stability is a key determinant of longevity and negligible senescence, age-related gene expression was examined in three tissues of the red sea urchin (Aristotle’s lantern muscle, esophagus and radial nerve cord). Genome-wide transcriptional profiling using RNA-Seq revealed remarkable stability in muscle and esophagus with very few age-related changes in gene expression. In contrast, expression of more than 900 genes was significantly altered with age in radial nerve cord including genes involved in nerve function, signaling, metabolism, cytoskeleton, transcriptional regulation and chromatin modification. Notably, there was an upregulation in expression of genes involved in synaptogenesis and axonogenesis suggesting enhanced nervous system activity with age. Among the signaling pathways affected by age, there was a downregulation in expression of key components of the mTOR signaling pathway and an upregulation of negative regulators of this pathway. This was accompanied by a reduction in expression of genes involved in protein synthesis and mitochondrial function and an increase in expression of genes that promote autophagy. Downregulation of the mTOR pathway together with the other observed changes reveals a unique age-related gene expression profile in the red sea urchin nervous system that may contribute to mitigation of the detrimental effects of aging in this long-lived animal.
Project description:We used CAGE-seq (Capped Analysis of Gene Expression with Sequencing) to profile eRNA expression and enhancer activity during embryogenesis of the sea urchin, Strongylocentrotus purpuratus. We identified >18,000 enhancers that were active during late oogenesis and early development and documented a burst of enhancer activation during cleavage and early blastula stages. Most enhancers were located near gene bodies and eRNA expression levels were highest for elements near core promoters. Transcriptional signals from enhancers generally paralleled the expression levels of likely target genes. Furthermore, enhancers near lineage-specific genes contained signatures of inputs from developmental gene regulatory networks deployed in those lineages. A large fraction (60%) of sea urchin enhancers previously shown to be active in transgenic reporter assays were associated with eRNA expression. Moreover, a large fraction (50%) of a representative subset of enhancers identified by eRNA profiling drove tissue-specific gene expression in isolation when tested by reporter assays. Our findings provide an atlas of developmental enhancers in a model sea urchin and support the utility of eRNA profiling as a tool for enhancer discovery and regulatory biology. The data generated in this study are publicly available at Echinobase (www.echinobase.org).
2021-06-30 | GSE169227 | GEO
Project description:Genomic characterization of the camarodont sea urchin Tripneustes kermadecensis
