ArticleFrontiers in zoology2007
A new look at the ventral nerve centre of Sagitta: implications for the phylogenetic position of Chaetognatha (arrow worms) and the evolution of the bilaterian nervous system.
Article in Frontiers in zoology, 2007. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 17 papers.
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Who cites it
17 citing papers in PubMed.
- Early nervous system development in the chaetognathFrontiers in cell and developmental biology · 2026Article
- Anterior-posterior patterning in the chaetognath Spadella cephaloptera informs bilaterian nervous system and tail evolution.Communications biology · 2025Article
- A fossilized ventral ganglion reveals a chaetognath affinity for Cambrian nectocaridids.Science advances · 2025Article
- Unfolding the ventral nerve center of chaetognaths.Neural development · 2024Article
- A giant stem-group chaetognath.Science advances · 2024Article
- Neurons and Glia Cells in Marine Invertebrates: An Update.Frontiers in neuroscience · 2020Review
- Xenacoelomorpha: a case of independent nervous system centralization?Philosophical transactions of the Royal Society of London. Series B, Biological sciences · 2016Article
- Evolving gene regulatory networks into cellular networks guiding adaptive behavior: an outline how single cells could have evolved into a centralized neurosensory system.Cell and tissue research · 2015Review
- Comparative analyses of olfactory systems in terrestrial crabs (Brachyura): evidence for aerial olfaction?PeerJ · 2015Article
- Evolutionary history of Chaetognatha inferred from molecular and morphological data: a case study for body plan simplification.Frontiers in zoology · 2014Article
- Anatomy and development of the larval nervous system in Echinococcus multilocularis.Frontiers in zoology · 2013Article
- Evolution of the let-7 microRNA family.RNA biology · 2012Article
- Invertebrate neurophylogeny: suggested terms and definitions for a neuroanatomical glossary.Frontiers in zoology · 2010Article
- Brain architecture of the largest living land arthropod, the Giant Robber Crab Birgus latro (Crustacea, Anomura, Coenobitidae): evidence for a prominent central olfactory pathway?Frontiers in zoology · 2010Article
- Brain architecture in the terrestrial hermit crab Coenobita clypeatus (Anomura, Coenobitidae), a crustacean with a good aerial sense of smell.BMC neuroscience · 2008Article
- Assembling the lophotrochozoan (=spiralian) tree of life.Philosophical transactions of the Royal Society of London. Series B, Biological sciences · 2008Review
- Chaetognath transcriptome reveals ancestral and unique features among bilaterians.Genome biology · 2008Article
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2 authors.
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Abstract
backgroundThe Chaetognatha (arrow worms) are a group of marine carnivores whose phylogenetic relationships are still vigorously debated. Molecular studies have as yet failed to come up with a stable hypothesis on their phylogenetic position. In a wide range of metazoans, the nervous system has proven to provide a wealth of characters for analysing phylogenetic relationships (neurophylogeny). Therefore, in the present study we explored the structure of the ventral nerve centre ("ventral ganglion") in Sagitta setosa with a set of histochemical and immunohistochemical markers.
resultsIn specimens that were immunolabeled for acetylated-alpha tubulin the ventral nerve centre appeared to be a condensed continuation of the peripheral intraepidermal nerve plexus. Yet, synapsin immunolocalization showed that the ventral nerve centre is organized into a highly ordered array of ca. 80 serially arranged microcompartments. Immunohistochemistry against RFamide revealed a set of serially arranged individually identifiable neurons in the ventral nerve centre that we charted in detail.
conclusionThe new information on the structure of the chaetognath nervous system is compared to previous descriptions of the ventral nerve centre which are critically evaluated. Our findings are discussed with regard to the debate on nervous system organisation in the last common bilaterian ancestor and with regard to the phylogenetic affinities of this Chaetognatha. We suggest to place the Chaetognatha within the Protostomia and argue against hypotheses which propose a deuterostome affinity of Chaetognatha or a sister-group relationship to all other Bilateria.
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