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- Biressi, A., et al.
(author)
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Wound healing and arm regeneration in Ophioderma longicaudum and Amphiura filiformis (Ophiuroidea, Echinodermata): comparative morphogenesis and histogenesis
- 2010
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In: Zoomorphology. - : Springer Science and Business Media LLC. - 0720-213X .- 1432-234X. ; 129:1, s. 1-19
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Journal article (peer-reviewed)abstract
- All species of the Ophiuroidea have exceptional regenerative capabilities; in particular, they can replace arms lost following traumatic or self-induced amputation. In order to reconstruct this complex phenomenon, we studied arm regeneration in two different ophiuroids, Ophioderma longicaudum (Retzius, 1805) and Amphiura filiformis O. F. Muller, 1776, which are quite distantly related. These species present contrasting regeneration and differentiation rates and differ in several ecological traits. The aim of this paper is to interpret the primary sequence of morphogenetic and histogenetic events leading to the complete reconstruction of a new arm, comparing the arm regenerative processes of these two ophiuroid species with those described in crinoids. Arm regeneration in ophiuroids is considered an epimorphic process in which new structures develop from a typical blastema formed from an accumulation of presumptive undifferentiated cells. Our results showed that although very different in some respects such as, for instance, the regeneration rate (0.17 mm/week for O. longicaudum and 0.99 mm/week for A. filiformis), morphogenetic and histogenetic aspects are surprisingly similar in both species. The regenerative process presents similar characteristics and follows a developmental scheme which can be subdivided into four phases: a repair phase, an early regenerative phase, an intermediate regenerative phase and an advanced regenerative phase. In terms of histogenesis, the regenerative events involve the development of new structures from migratory pluripotent cells, which proliferate actively, in addition in both cases there is a significant contribution from dedifferentiated cells, in particular dedifferentiating myocytes, although to varying extents. This evidence confirms the plasticity of the regenerative phenomenon in echinoderms, which can apparently follow different pathways in terms of growth and morphogenesis, but nevertheless involve both epimorphic and morphallactic contributions at the cellular level.
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| 3. |
- Olinski, Robert, et al.
(author)
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Three insulin-relaxin-like genes in Ciona intestinalis
- 2006
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In: Peptides. - : Elsevier BV. - 0196-9781 .- 1873-5169. ; 27:11, s. 2535-2546
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Journal article (peer-reviewed)abstract
- The Ciona intestinalis genome harbors three insulin-like genes: INS-L1, -L2 and -L3. Conserved synteny between the Ciona-human genomes predicts that Ciona INS-Ls are orthologous to the vertebrate insulin-relaxin family, but this relation cannot be inferred from molecular phylogeny. A conserved protein core with six cysteines; typical arrangement of B-, C- and A-protein domains; pro-protein maturation mode; and putative insulin receptor-binding sites were identified in Ciona INS-L proteins. ESTs used to assemble exonic sequences of INS-Ls combined with qRT-PCR analysis provided evidence that the predicted genes are expressed in the developing and adult Ciona. Our results support that Ciona INS-L1 is orthologous to the vertebrate insulin-like/relaxin genes, INS-L2 to insulin genies and INS-L3 to IGF genes. Our analysis also implies that the insulin-like/relaxin ancestor switched receptor type from tyrosine kinase- to GPCR-type, whereas insulin-IGF subfamily retained the tyrosine kinase-type of receptor. We propose that this receptor-switch occurred after the time when urochordates branched from the common chordate lineage, but before the two genome-duplications at the root of the vertebrates. (c) 2006 Elsevier Inc. All rights reserved.
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| 4. |
- Skriver Hansen, Andreas, 1983, et al.
(author)
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Synthesizing knowledge and evidence to inform the management of coastal seas’ biodiversity and NCPs – a case study from Sweden
- 2022
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In: Presentation given at ECSA 59, 5-8 September 2022, Kursaal, San Sebastian, Spain. - Essen : University of Duisburg Essen, Faculty of Biology, Aquatic Ecology.
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Conference paper (other academic/artistic)abstract
- While being among the most productive ecosystems on earth, coastal ecosystems are heavily impacted by anthropogenic causes on land and at sea. Fisheries, nutrient discharges from land uses and global climate change, for example, adversely affect coastal seas’ biodiversity, functioning and related nature’s contributions to people (NCPs). Data and knowledge of particular cause-effect relationships in these complex systems is often insufficient or missing. Therefore, a coupled model framework was developed that allows the combination of evidence from environmental monitoring data, literature, expert knowledge and stakeholder interviews and thereby enables the exploration of causal relations between human-induced environmental change, biodiversity and NCPs. The framework was applied to the Kosterhavet National Park in Sweden. First, a Bayesian Belief Network (BBN) was built to link anthropogenic land and sea uses and climate change via abiotic and biotic cause-and-effect relationships to two ecological key species in the national park: eelgrass (Zostera marina) and northern shrimp (Pandalus borealis). Subsequently, social-cultural and social-economic cause-and-consequence chains were developed, to derive the potential implications of changes in eelgrass coverage and shrimp stock on human well-being. It was shown that the sustainable management of the two target species in Kosterhavet National Park requires local management in the park (e.g. recreational use and fishery) and regional management across coastal water bodies (e.g. nutrient management). Significant declines in eelgrass and northern shrimp were found to impact the people’s place attachment, tradition, knowledge and identity more than their regional economy. The coupled model framework is currently implemented as an online tool to facilitate its application and support decision making.
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