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Current Topics in Developmental Biology 2016Primordial germ cells are usually made early in the development of an organism. These are the mother of all stem cells that are necessary for propagation of the species,... (Review)
Review
Primordial germ cells are usually made early in the development of an organism. These are the mother of all stem cells that are necessary for propagation of the species, yet use highly diverse mechanisms between organisms. How they are specified, and when and where they form, are central to developmental biology. Using diverse organisms to study this development is illuminating for understanding the mechanics these cells use in this essential function and for identifying the breadth of evolutionary changes that have occurred between species. This essay emphasizes how echinoderms may contribute to the patchwork quilt of our understanding of germ line formation during embryogenesis.
Topics: Animals; Biological Evolution; Echinodermata; Embryo, Nonmammalian; Embryonic Development; Gene Expression Regulation, Developmental; Germ Cells
PubMed: 26970000
DOI: 10.1016/bs.ctdb.2015.11.030 -
Current Topics in Developmental Biology 2022The micromeres of the sea urchin embryo are distinct from other blastomeres. After they arise through an asymmetric cell division at the 8- to 16-cell stage, micromeres...
The micromeres of the sea urchin embryo are distinct from other blastomeres. After they arise through an asymmetric cell division at the 8- to 16-cell stage, micromeres immediately function as organizers. They also commit themselves to specific cell fates such as larval skeletogenic cells and primordial germ cells, while other blastomeres remain plastic and uncommitted at the 16-cell stage. In the phylum Echinodermata, only the sea urchin (class Echinoidea) embryo forms micromeres that serve as apparent organizers during early embryogenesis. Therefore, it is considered that micromeres are the derived features and that modification(s) of the developmental system allowed evolutionary introduction of this unique cell lineage. In this chapter, we summarize the both historic and recent observations that demonstrate unique properties of micromeres and discuss how this lineage of micromeres may have arisen during echinoderm evolution.
Topics: Animals; Blastomeres; Echinodermata; Embryo, Nonmammalian; Embryonic Development; Sea Urchins
PubMed: 35152984
DOI: 10.1016/bs.ctdb.2021.10.008 -
Methods in Molecular Biology (Clifton,... 2022Echinoderms are marine invertebrate deuterostomes known for their amazing regenerative abilities throughout all life stages. Though some species can undergo whole-body...
Echinoderms are marine invertebrate deuterostomes known for their amazing regenerative abilities throughout all life stages. Though some species can undergo whole-body regeneration (WBR), others exhibit more restricted regenerative capabilities. Asteroidea (starfish) comprise one of the few echinoderm taxa capable of undergoing WBR. Indeed, some starfish species can restore all tissues and organs not only during larval stages, but also from arm fragments as adults. Arm explants have been used to study cells, tissues and genes involved in starfish regeneration. Here, we describe methods for obtaining and studying regeneration of arm explants in starfish, in particular animal collection and husbandry, preparation of arm explants, regeneration tests, microscopic anatomy techniques (including transmission electron microscopy, TEM) used to analyze the regenerating explant tissues and cells plus a downstream RNA extraction protocol needed for subsequent molecular investigations.
Topics: Animals; Echinodermata; Larva; Starfish
PubMed: 35359313
DOI: 10.1007/978-1-0716-2172-1_14 -
Cells Feb 2022Although a recent genomic survey revealed its ancient evolutionary origin in the animal kingdom, retinoic acid (RA) signaling was previously thought to be unique to... (Review)
Review
Although a recent genomic survey revealed its ancient evolutionary origin in the animal kingdom, retinoic acid (RA) signaling was previously thought to be unique to chordates. Echinoderms are of critical interest in researching the evolutionary history of RA signaling, as they represent a basal group of deuterostomes. Furthermore, our previous works have suggested that echinoderms may possess the ancestral function of RA signaling for metamorphosis regulation. In this paper, to facilitate future studies of RA signaling in echinoderms, we provide an overview of RA machinery in echinoderms, identify its signaling components, and discuss its developmental role.
Topics: Animals; Biological Evolution; Chordata; Echinodermata; Signal Transduction; Tretinoin
PubMed: 35159332
DOI: 10.3390/cells11030523 -
Cell Calcium Jan 2013Calcium signaling in cells directs diverse physiological processes. The calcium waves triggered by fertilization is a highly conserved calcium signaling event essential... (Review)
Review
Calcium signaling in cells directs diverse physiological processes. The calcium waves triggered by fertilization is a highly conserved calcium signaling event essential for egg activation, and has been documented in every egg tested. This activity is one of the few highly conserved events of egg activation through the course of evolution. Echinoderm eggs, as well as many other cell types, have three main intracellular Ca(2+) mobilizing messengers - IP3, cADPR and NAADP. Both cADPR and NAADP were identified as Ca(2+) mobilizing messengers using the sea urchin egg homogenate, and this experimental system, along with the intact urchin and starfish oocyte/egg, continues to be a vital tool for investigating the mechanism of action of calcium signals. While many of the major regulatory steps of the IP3 pathway are well resolved, both cADPR and NAADP remain understudied in terms of our understanding of the fundamental process of egg activation at fertilization. Recently, NAADP has been shown to trigger Ca(2+) release from acidic vesicles, separately from the ER, and a new class of calcium channels, the two-pore channels (TPCs), was identified as the likely targets for this messenger. Moreover, it was found that both cADPR and NAADP can be synthesized by the same family of enzymes, the ADP-rybosyl cyclases (ARCs). In this context of increasing amount of information, the potential coupling and functional roles of different messengers, intracellular stores and channels in the formation of the fertilization calcium wave in echinoderms will be critically evaluated.
Topics: Animals; Calcium Channels; Calcium Signaling; Cyclic ADP-Ribose; Echinodermata; Fertilization; NADP
PubMed: 23218671
DOI: 10.1016/j.ceca.2012.11.011 -
PloS One 2020Several starfish (Echinodermata, Asteroidea) are keystone species of marine ecosystems, but some of the species are difficult to identify using morphological criteria...
Several starfish (Echinodermata, Asteroidea) are keystone species of marine ecosystems, but some of the species are difficult to identify using morphological criteria only. The common sunstar, Crossaster papposus (Linnaeus, 1767), is a conspicuous species with a wide circumboreal distribution. In 1900, a closely similar species, C. squamatus (Döderlein, 1900) was described from the NE Atlantic Ocean, but subsequent authors have differed in their views on whether this is a valid taxon or rather an ecotype associated with temperature variations. We assessed the differentiating morphological characters of specimens from Norwegian and Greenland waters identified as C. papposus and C. squamatus and compared their distributions in the NE Atlantic as inferred from research cruises. The field data show that C. papposus is found mainly in temperate and shallow waters, whereas C. squamatus resides on the shelf-break in colder, mixed water masses. Intraspecific diversity and interspecific genetic differentiation of the two putative species, and their phylogenetic relationships to several Crossaster congeners worldwide, were explored using mitochondrial and nuclear DNA sequences. The molecular evidence suggests that C. papposus is the more diverse and geographically structured taxon, in line with its wide distribution. C. papposus and C. squamatus are closely related, yet clearly distinct taxa, while C. papposus and C. multispinus H.L. Clark, 1916, the latter from the South Pacific Ocean, are closely related, possibly sister taxa.
Topics: Animal Distribution; Animals; Atlantic Ocean; Cell Nucleus; DNA, Mitochondrial; Greenland; Norway; Pacific Ocean; Phylogeny; Sequence Analysis, DNA; Starfish; Temperature
PubMed: 31910238
DOI: 10.1371/journal.pone.0227223 -
Bioinspiration & Biomimetics Nov 2020The endoskeleton of echinoderms () is of mesodermal origin and consists of cells, organic components, as well as an inorganic mineral matrix. The echinoderm skeleton... (Review)
Review
The endoskeleton of echinoderms () is of mesodermal origin and consists of cells, organic components, as well as an inorganic mineral matrix. The echinoderm skeleton forms a complex lattice-system, which represents a model structure for naturally inspired engineering in terms of construction, mechanical behaviour and functional design. The sea urchin () endoskeleton consists of three main structural components: test, dental apparatus and accessory appendages. Although, all parts of the echinoid skeleton consist of the same basic material, their microstructure displays a great potential in meeting several mechanical needs according to a direct and clear structure-function relationship. This versatility has allowed the echinoid skeleton to adapt to different activities such as structural support, defence, feeding, burrowing and cleaning. Although, constrained by energy and resource efficiency, many of the structures found in the echinoid skeleton are optimized in terms of functional performances. Therefore, these structures can be used as role models for bio-inspired solutions in various industrial sectors such as building constructions, robotics, biomedical and material engineering. The present review provides an overview of previous mechanical and biomimetic research on the echinoid endoskeleton, describing the current state of knowledge and providing a reference for future studies.
Topics: Animals; Biomimetics; Echinodermata; Sea Urchins
PubMed: 32927446
DOI: 10.1088/1748-3190/abb86b -
Molecular Reproduction and Development Sep 2014One quarter of eukaryotic genes encode membrane proteins. These include nearly 1,000 transporters that translocate nutrients, signaling molecules, and xenobiotics across... (Review)
Review
One quarter of eukaryotic genes encode membrane proteins. These include nearly 1,000 transporters that translocate nutrients, signaling molecules, and xenobiotics across membranes. While it is well appreciated that membrane transport is critical for development, the specific roles of many transporters have remained cryptic, in part because of their abundance and the diversity of their substrates. Multidrug resistance ATP-binding cassette (ABC) efflux transporters are one example of cryptic membrane proteins. Although most organisms utilize these ABC transporters during embryonic development, many of these transporters have broad substrate specificity, and their developmental functions remain incompletely understood. Here, we review advances in our understanding of ABC transporters in sea urchin embryos, and methods developed to spatially and temporally map these proteins. These studies reveal that multifunctional transporters are required for signaling, homeostasis, and protection of the embryo, and shed light on how they are integrated into ancestral developmental pathways recapitulated in disease.
Topics: ATP-Binding Cassette Transporters; Animals; Sea Urchins
PubMed: 25156004
DOI: 10.1002/mrd.22357 -
International Journal of Molecular... Sep 2023Aestivation is considered to be one of the "purest" hypometabolic states in nature, as it involves aerobic dormancy that can be induced and sustained without complex... (Review)
Review
Aestivation is considered to be one of the "purest" hypometabolic states in nature, as it involves aerobic dormancy that can be induced and sustained without complex factors. Animals that undergo aestivation to protect themselves from environmental stressors such as high temperatures, droughts, and food shortages. However, this shift in body metabolism presents new challenges for survival, including oxidative stress upon awakening from aestivation, accumulation of toxic metabolites, changes in energy sources, adjustments to immune status, muscle atrophy due to prolonged immobility, and degeneration of internal organs due to prolonged food deprivation. In this review, we summarize the physiological and metabolic strategies, key regulatory factors, and networks utilized by aestivating animals to address the aforementioned components of aestivation. Furthermore, we present a comprehensive overview of the advancements made in aestivation research across major species, including amphibians, fish, reptiles, annelids, mollusks, and echinoderms, categorized according to their respective evolutionary positions. This approach offers a distinct perspective for comparative analysis, facilitating an understanding of the shared traits and unique features of aestivation across different groups of organisms.
Topics: Animals; Estivation; Biological Evolution; Droughts; Echinodermata; Energy-Generating Resources
PubMed: 37762394
DOI: 10.3390/ijms241814093 -
Ecology Mar 2022Sea stars (Echinodermata: Asteroidea) are a key component of Southern Ocean benthos, with 16% of the known sea star species living there. In temperate marine...
Sea stars (Echinodermata: Asteroidea) are a key component of Southern Ocean benthos, with 16% of the known sea star species living there. In temperate marine environments, sea stars commonly play an important role in food webs, acting as keystone species. However, trophic ecology and functional role of Southern Ocean sea stars are still poorly known, notably due to the scarcity of large-scale studies. Here, we report 24,332 trophic marker (stable isotopes and elemental contents of C, N, and S of tegument and/or tube feet) and biometric (arm length, disk radius, arm to disk ratio) measurements in 2,456 specimens of sea stars. Samples were collected between 12 January 1985 and 8 October 2017 in numerous locations along the Antarctic littoral and subantarctic islands. The spatial scope of the data set covers a significant portion of the Southern Ocean (47.717° S to 86.273° S; 127.767° W to 162.201° E; depth, 6-5,338 m). The data set contains 133 distinct taxa, including 72 currently accepted species spanning 51 genera, 20 families, and multiple feeding guilds/functional groups (suspension feeders, sediment feeders, omnivores, predators of mobile or sessile prey). For 505 specimens, mitochondrial CO1 genes were sequenced to confirm and/or refine taxonomic identifications, and those sequences are already publicly available through the Barcode of Life Data System. This number will grow in the future, as molecular analyses are still in progress. Overall, thanks to its large taxonomic, spatial, and temporal extent, as well as its integrative nature (combining genetic, morphological, and ecological data), this data set can be of wide interest to Southern Ocean ecologists, invertebrate zoologists, benthic ecologists, and environmental managers dealing with associated areas. Please cite this data paper in research products derived from the data set, which is freely available without copyright restrictions.
Topics: Animals; Biometry; Ecosystem; Food Chain; Humans; Oceans and Seas; Starfish
PubMed: 34921398
DOI: 10.1002/ecy.3611