Project description:Owenia fusiformis is an ancestral sister group to the annelids, it has a unique "head larvae" type named mitraria larvae. To identify the gene expressed in different tissues, especially the gene expressed in head region, we dissected the 5 female worms and 1 male worm to get 9 different tissues, and extracted their RNA. The sequencing were performed on BGISEQ-500 platform, and the mapping were done with Kallisto and normalization was performed with DEseq2.
Project description:Owenia fusiformis has a unique mitraria larvae form which is different to other marine spiralians. we utilize RNA-seq and ATAC-seq to profile the gene expression and chromatin accessibility to understand their development and evolution.
Project description:Owenia fusiformis has a unique mitraria larvae form which is different to other marine spiralians. we utilize RNA-seq and ATAC-seq to profile the gene expression and chromatin accessibility dynamics to understand their development and evolution.
Project description:BackgroundThe evolutionary origins of animal nervous systems remain contentious because we still have a limited understanding of neural development in most major animal clades. Annelids - a species-rich group with centralised nervous systems - have played central roles in hypotheses about the origins of animal nervous systems. However, most studies have focused on adults of deeply nested species in the annelid tree. Recently, Owenia fusiformis has emerged as an informative species to reconstruct ancestral traits in Annelida, given its phylogenetic position within the sister clade to all remaining annelids.MethodsCombining immunohistochemistry of the conserved neuropeptides FVamide-lir, RYamide-lir, RGWamide-lir and MIP-lir with gene expression, we comprehensively characterise neural development from larva to adulthood in Owenia fusiformis.ResultsThe early larval nervous system comprises a neuropeptide-rich apical organ connected through peripheral nerves to a prototroch ring and the chaetal sac. There are seven sensory neurons in the prototroch. A bilobed brain forms below the apical organ and connects to the ventral nerve cord of the developing juvenile. During metamorphosis, the brain compresses, becoming ring-shaped, and the trunk nervous system develops several longitudinal cords and segmented lateral nerves.ConclusionsOur findings reveal the formation and reorganisation of the nervous system during the life cycle of O. fusiformis, an early-branching annelid. Despite its apparent neuroanatomical simplicity, this species has a diverse peptidergic nervous system, exhibiting morphological similarities with other annelids, particularly at the larval stages. Our work supports the importance of neuropeptides in animal nervous systems and highlights how neuropeptides are differentially used throughout development.
Project description:The developmental transcriptome and epigenome of Owenia fusiformis reveal the development and evolution of mitraria larvae [dataset2]
