Project description:Positional RNA-sequencing of isolated Hydra body pieces and RNA-sequencing of fully regenerated Hydra animal was combined with RNA-sequencing of actively regenerating spheroids (see submission E-MTAB-9672) in order to elucidate the role of tissue stretching on regeneration and body pattern formation.
Project description:The Chinese sturgeon (Acipenser sinensis) is anadromous fish distributed in Yangtze River and East China Sea. In this study, we reported cleft-palate Chinese sturgeons in artificial population for the first time. In order to explore the genetic basis of palate malformation in A. sinensis, Illumina RNA-seq technology was used to analyze the transcriptome data of normal and cleft-palate individuals in farmed Chinese sturgeons. Raw reads were obtained and assembled into 808,612 unigenes, with an average length of 509.33 bp and an N50 of 574 bp. Sequence similarity analyses against four public databases (Nr, Uniprot, KEGG and COGs) found 158,642 unigenes that can be annotated. GABAergic synapse and TGF-β signal pathway were the most two enriched pathways with high Richfactor in the analyses of different expressed genes. In these two signal pathways, six genes (GABRA4, GS, GNS, S6K, PITX2, and BMP8) were found as cleft-palate genes in Chinese sturgeon. These findings contribute to our understanding of the genetic basis of cleft palate in sturgeon, while simultaneously adding to our knowledge about craniofacial development.
Project description:Hydra has long been studied for its remarkable ability to regenerate its head. Previous studies focusing on molecular mechanisms of axial patterning and head regeneration using a candidate gene approach have revealed a central role for the canonical Wnt pathway. We performed a global gene expression analysis during Hydra magnipapillata head regeneration using RNA-seq to identify additional genes that are transcriptionally regulated during the regeneration of the head organizer in hydra. Differential expression analysis revealed a set of 4,978 genes with significant changes during a 48-hour head regeneration time-course that includes many key genes in the Wnt, TGF-M-NM-2/BMP and MAP kinase pathways. We observed the differential regulation of several genes that are part of the epithelial-to-mesenchymal transition in bilaterians such as Snail. We assembled 806 novel putative lincRNAs with 176 of these are differentially expressed during the time course. We observed the coordinated transcriptional regulation of several factors that regulate the effective pool of free M-NM-2-catenin that together synergize to increase the amount of M-NM-2-catenin available for transcriptional regulation of downstream genes. The differential expression of Snail and some of its interacting regulators and downstream targets suggests that a partial-EMT-like response is involved in hydra head regeneration. This time-course is a valuable resource for the study of the transcriptional dynamics of head regeneration in hydra. mRNA profiling of regenerating head from 6 time points post bisection of Hydra head (H. magnipapillata), generated by deep sequencing, in duplicates, using Illumina HiSeq2500.
Project description:The molecular nature of malignant tumors is well studied in vertebrates, while their evolutionary origin remains unknown. In particular, there is no evidence for naturally occurring malignant tumors in pre-bilaterian animals, such as sponges and cnidarians. This is somewhat surprising given that recent computational studies have predicted that all metazoans are prone to develop tumors. Here we provide first evidence for naturally occurring tumors in Hydra oligactis. Histological, cellular and molecular data reveal that these tumors are transplantable and caused by differentiation arrest of female gametes. Growth of tumor cells is independent from the cellular environment. Tumor bearing polyps have significantly reduced fitness. In addition, Hydra tumors show a greatly altered transcriptome that mimics expression shifts in vertebrate cancers. Therefore, this study shows, that invasive tumors have deep roots in animal phylogeny, and that early branching animals may be informative in revealing the fundamental mechanisms of tumorigenesis. We compared four samples of Hydra oligactis tumor-bearing animals to three samples of female polyps undergoing oogenesis and six samples of female asexual control polyps