ArticlePloS one2014
Controversies surrounding segments and parasegments in onychophora: insights from the expression patterns of four "segment polarity genes" in the peripatopsid Euperipatoides rowelli.
Article in PloS one, 2014. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 23 papers.
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Who cites it
23 citing papers in PubMed, 56 citations in OpenAlex.
- Quantifying Evolutionary Dynamics of Arthropodization and Arthrodization.BioEssays : news and reviews in molecular, cellular and developmental biology · 2026Review
- FGF and BMP pathway genes are expressed in segmentally iterated domains during segmentation of germ layers in a tardigrade.bioRxiv : the preprint server for biology · 2025Article
- Hedgehog Signaling during Gut Formation in the Freshwater Leech, Helobdella austinensis.Cells, tissues, organs · 2025Article
- Single-cell sequencing suggests a conserved function of Hedgehog-signalling in spider eye development.EvoDevo · 2024Article
- Interlocking of co-opted developmental gene networks in Drosophila and the evolution of pre-adaptive novelty.Nature communications · 2023Article
- Review of extra-embryonic tissues in the closest arthropod relatives, onychophorans and tardigrades.Philosophical transactions of the Royal Society of London. Series B, Biological sciences · 2022Review
- Lack of evidence for conserved parasegmental grooves in arthropods.Development genes and evolution · 2022Article
- The velvet worm brain unveils homologies and evolutionary novelties across panarthropods.BMC biology · 2022Article
- Extensive loss of Wnt genes in Tardigrada.BMC ecology and evolution · 2021Article
- Expression of NK genes that are not part of the NK cluster in the onychophoran Euperipatoides rowelli (Peripatopsidae).BMC developmental biology · 2019Article
- Article
- Embryonic expression of a Long Toll (Loto) gene in the onychophorans Euperipatoides kanangrensis and Cephalofovea clandestina.Development genes and evolution · 2018Article
- Embryonic expression patterns and phylogenetic analysis of panarthropod sox genes: insight into nervous system development, segmentation and gonadogenesis.BMC evolutionary biology · 2018Article
- Gene expression analysis of potential morphogen signalling modifying factors in Panarthropoda.EvoDevo · 2018Article
- Expression of NK cluster genes in the onychophoranEvoDevo · 2018Article
- The nervous and visual systems of onychophorans and tardigrades: learning about arthropod evolution from their closest relatives.Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology · 2017Review
- Assessing segmental versus non-segmental features in the ventral nervous system of onychophorans (velvet worms).BMC evolutionary biology · 2017Article
- Gene expression analysis reveals that Delta/Notch signalling is not involved in onychophoran segmentation.Development genes and evolution · 2016Article
- The impact of taphonomic data on phylogenetic resolution: Helenodora inopinata (Carboniferous, Mazon Creek Lagerstätte) and the onychophoran stem lineage.BMC evolutionary biology · 2016Article
- An embryological perspective on the early arthropod fossil record.BMC evolutionary biology · 2015Article
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2 authors at 1 institution in 1 country.
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Abstract
Arthropods typically show two types of segmentation: the embryonic parasegments and the adult segments that lie out of register with each other. Such a dual nature of body segmentation has not been described from Onychophora, one of the closest arthropod relatives. Hence, it is unclear whether onychophorans have segments, parasegments, or both, and which of these features was present in the last common ancestor of Onychophora and Arthropoda. To address this issue, we analysed the expression patterns of the "segment polarity genes" engrailed, cubitus interruptus, wingless and hedgehog in embryos of the onychophoran Euperipatoides rowelli. Our data revealed that these genes are expressed in repeated sets with a specific anterior-to-posterior order along the body in embryos of E. rowelli. In contrast to arthropods, the expression occurs after the segmental boundaries have formed. Moreover, the initial segmental furrow retains its position within the engrailed domain throughout development, whereas no new furrow is formed posterior to this domain. This suggests that no re-segmentation of the embryo occurs in E. rowelli. Irrespective of whether or not there is a morphological or genetic manifestation of parasegments in Onychophora, our data clearly show that parasegments, even if present, cannot be regarded as the initial metameric units of the onychophoran embryo, because the expression of key genes that define the parasegmental boundaries in arthropods occurs after the segmental boundaries have formed. This is in contrast to arthropods, in which parasegments rather than segments are the initial metameric units of the embryo. Our data further revealed that the expression patterns of "segment polarity genes" correspond to organogenesis rather than segment formation. This is in line with the concept of segmentation as a result of concerted evolution of individual periodic structures rather than with the interpretation of 'segments' as holistic units.
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