Functional anatomy of the valves in the ambulacral system of sea urchins (Echinodermata, Echinoida)

Märkel, Konrad; Röser, Ursula

doi:10.1007/bf01632907

Cited by 8 publications

(4 citation statements)

References 14 publications

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“…The preodontoblasts originating at the aboral plumula arise from a mixed population of coelomocytes. The individual monocytes condense at the outer surface of the plumula (4, 5) just under the epithelial layer, where they fuse and become multinucleated cells, which form sheetlike syncytial layers (6). Calcium carbonate mineral forms at calcification sites between the cellular layers, with the mineral deposition related to the syncytial plasma membranes (7–9).…”

mentioning

confidence: 99%

Echinoderm Phosphorylated Matrix Proteins UTMP16 and UTMP19 Have Different Functions in Sea Urchin Tooth Mineralization

Alvares

Dixit

Lux

et al. 2009

Journal of Biological Chemistry

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Studies of mineralization of embryonic spicules and of the sea urchin genome have identified several putative mineralization-related proteins. These predicted proteins have not been isolated or confirmed in mature mineralized tissues. Mature Lytechinus variegatus teeth were demineralized with 0.6 n HCl after prior removal of non-mineralized constituents with 4.0 m guanidinium HCl. The HCl-extracted proteins were fractionated on ceramic hydroxyapatite and separated into bound and unbound pools. Gel electrophoresis compared the protein distributions. The differentially present bands were purified and digested with trypsin, and the tryptic peptides were separated by high pressure liquid chromatography. NH2-terminal sequences were determined by Edman degradation and compared with the genomic sequence bank data. Two of the putative mineralization-related proteins were found. Their complete amino acid sequences were cloned from our L. variegatus cDNA library. Apatite-binding UTMP16 was found to be present in two isoforms; both isoforms had a signal sequence, a Ser-Asp-rich extracellular matrix domain, and a transmembrane and cytosolic insertion sequence. UTMP19, although rich in Glu and Thr did not bind to apatite. It had neither signal peptide nor transmembrane domain but did have typical nuclear localization and nuclear exit signal sequences. Both proteins were phosphorylated and good substrates for phosphatase. Immunolocalization studies with anti-UTMP16 show it to concentrate at the syncytial membranes in contact with the mineral. On the basis of our TOF-SIMS analyses of magnesium ion and Asp mapping of the mineral phase composition, we speculate that UTMP16 may be important in establishing the high magnesium columns that fuse the calcite plates together to enhance the mechanical strength of the mineralized tooth.

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confidence: 99%

Echinoderm Phosphorylated Matrix Proteins UTMP16 and UTMP19 Have Different Functions in Sea Urchin Tooth Mineralization

Alvares

Dixit

Lux

et al. 2009

Journal of Biological Chemistry

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“…A unique feature of echinoid, holothurid, and asteroid bodies are the tube feet, which are more prominent in sea urchins. These appendages form part of the echinoid's hydraulic (ambulacral) system with each tube foot acting semi-autonomously [17]. Tube feet are filled with water pumped in from the surrounding environment and held under hydrostatic pressure through a series of interconnecting valves and channels.…”

Section: Tube Feet and Their Nervous Controlmentioning

confidence: 99%

Sea Urchins as an Inspiration for Robotic Designs

Stiefel

Barrett

2018

JMSE

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Neuromorphic engineering is the approach to intelligent machine design inspired by nature. Here, we outline possible robotic design principles derived from the neural and motor systems of sea urchins (Echinoida). Firstly, we review the neurobiology and locomotor systems of sea urchins, with a comparative emphasis on differences to animals with a more centralized nervous system. We discuss the functioning and enervation of the tube feet, pedicellariae, and spines, including the limited autonomy of these structures. We outline the design principles behind the sea urchin nervous system. We discuss the current approaches of adapting these principles to robotics, such as sucker-like structures inspired by tube feet and a robotic adaptation of the sea urchin jaw, as well as future directions and possible limitations to using these principles in robots.

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“…These single crystals [50] form inside a syncytium [51], a membrane envelope produced by many cells. The cells provide the necessary raw materials for constructing the growing crystals [52,53]. The crystal grows out of an aqueous solution saturated with calcium carbonate [54].…”

Section: Biological Control At Nucleation Levelmentioning

confidence: 99%