Publications by authors named "Chris Amemiya"

Human genetic studies have nominated cadherin-like and PC-esterase domain-containing 1 () as a candidate target gene mediating bone mineral density (BMD) and fracture risk heritability. Recent efforts to define the role of in bone in mouse and human models have revealed complex alternative splicing and inconsistent results arising from gene targeting, making its function in bone difficult to interpret. To better understand the role of in adult bone mass and morphology, we conducted a comprehensive genetic and phenotypic analysis of in zebrafish, an emerging model for bone and mineral research.

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Human genetic studies have nominated Cadherin-like and PC-esterase Domain-containing 1 () as a candidate target gene mediating bone mineral density (BMD) and fracture risk heritability. Recent efforts to define the role of in bone in mouse and human models have revealed complex alternative splicing and inconsistent results arising from gene targeting, making its function in bone difficult to interpret. To better understand the role of in adult bone mass and morphology, we conducted a comprehensive genetic and phenotypic analysis of in zebrafish, an emerging model for bone and mineral research.

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Article Synopsis
  • Developmental biology isn't as popular or well-funded as it used to be, and other science fields are getting more attention instead.
  • A group of scientists from different parts of developmental biology met to discuss problems that are slowing down new discoveries and to suggest ways to fix them.
  • They want to "rebrand" the field, get more funding, encourage teamwork between different science areas, improve how science is taught, communicate better, and make sure everyone has equal opportunities and resources.
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Cnidarians are commonly recognized as sea jellies, corals, or complex colonies such as the Portuguese man-of-war. While some cnidarians possess rigid internal calcareous skeletons (e.g.

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Terrestrialization is an extreme physiological adaptation by which African lungfish survive dry seasons. For months and up to several years, lungfish live inside a dry mucus cocoon that protects them from desiccation. Light and electron microscopy reveal that the lungfish cocoon is a living tissue that traps bacteria.

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  • Cartilaginous fishes use Ampullae of Lorenzini (AoL) to sense electric fields through gel-filled sensory organs.
  • Recent research clarified the structural properties of AoL gel, suggesting it is colloidal, using microscopy and small-angle X-ray scattering techniques.
  • The study found that while proteins contribute to the gel's viscosity, they do not significantly affect its proton conductivity, paving the way for further exploration of molecular interactions within AoL gel at the nanoscale.
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Agnathans possess a convergent adaptive immune system in comparison to that of jawed vertebrates. In lieu of immunoglobulins, agnathans deploy variable lymphocyte receptors (VLRs), single chain protein effector molecules consisting of leucine rich repeat modules. Foundational work for this discovery utilized the parasitic sea lamprey, Petromyzon marinus.

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We previously reported that the polysaccharide chitin, a key component of arthropod exoskeletons and fungal cell walls, is endogenously produced by fishes and amphibians in spite of the widely held view that it was not synthesized by vertebrates [1]. Genes encoding chitin synthase enzymes were found in the genomes of a number of fishes and amphibians and shown to be correspondingly expressed at the sites where chitin was localized [1,2]. In this report, we present evidence suggesting that chitin is prevalent within the specialized electrosensory organs of cartilaginous fishes (Chondrichthyes).

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The variable lymphocyte receptors (VLRs) consist of leucine rich repeats (LRRs) and comprise the humoral antibodies produced by lampreys and hagfishes. The diversity of the molecules is generated by stepwise genomic rearrangements of LRR cassettes dispersed throughout the VLRB locus. Previously, target-specific monovalent VLRB antibodies were isolated from sea lamprey larvae after immunization with model antigens.

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The analysis of samples from unsequenced and/or understudied species as well as samples where the proteome is derived from multiple organisms poses two key questions. The first is whether the proteomic data obtained from an unusual sample type even contains peptide tandem mass spectra. The second question is whether an appropriate protein sequence database is available for proteomic searches.

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The neural crest (NC) is an embryonic cell population that contributes to key vertebrate-specific features including the craniofacial skeleton and peripheral nervous system. Here we examine the transcriptional and epigenomic profiles of NC cells in the sea lamprey, in order to gain insight into the ancestral state of the NC gene regulatory network (GRN). Transcriptome analyses identify clusters of co-regulated genes during NC specification and migration that show high conservation across vertebrates but also identify transcription factors (TFs) and cell-adhesion molecules not previously implicated in NC migration.

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Biological materials such as chiton tooth, squid beak, and byssal threads of bivalves have inspired the development of new technologies. To this end, we have characterized the acellular components in the buccal mass of the terrestrial slug Ariolimax californicus (banana slug). These components are the radula, the jaw, and the odontophore.

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Article Synopsis
  • The article was originally published without open access, but this has now been fixed and is noted in all versions.
  • An error regarding Robb Krumlauf's affiliation, indicating equal contribution, was missing in the original PDF but has been corrected.
  • Both the open access status and the authorship issue have been addressed to reflect accurate information.
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Haematopoietic stem and progenitor cells (HSPCs) require a specific microenvironment, the haematopoietic niche, which regulates HSPC behaviour. The location of this niche varies across species, but the evolutionary pressures that drive HSPCs to different microenvironments remain unknown. The niche is located in the bone marrow in adult mammals, whereas it is found in other locations in non-mammalian vertebrates, for example, in the kidney marrow in teleost fish.

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  • The article originally had the incorrect addresses for authors Dorit Hockman and Chris Amemiya swapped.
  • This mistake has been fixed in both the HTML and PDF formats of the article.
  • The correction ensures that readers can now find the right contact information for the authors.
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  • The sea lamprey serves as a valuable model for understanding vertebrate evolution due to its unique genomic features.
  • A new genome assembly reveals that chromosome and whole-genome duplications significantly influenced both lamprey and ancestral vertebrate evolution, including the organization of HOX gene clusters.
  • The research highlights the elimination of specific genes during early development in lampreys and suggests regulatory similarities with gene silencing mechanisms in other vertebrates, opening avenues for further evolutionary and biological studies.
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The biological material, chitin, is present in nature in three allomorphic forms: α, β and γ. Whereas most studies have dealt with α- and β-chitin, only few investigations have focused on γ-chitin, whose structural and physicochemical properties have not been well delineated. In this study, chitin obtained for the first time from the cocoon of the moth (Orgyia dubia) was subjected to extensive physicochemical analyses and examined, in parallel, with α-chitin from exoskeleton of a freshwater crab and β-chitin from cuttlebone of the common cuttlefish.

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Activation-induced cytidine deaminase (AID) is a genome-mutating enzyme that initiates class switch recombination and somatic hypermutation of antibodies in jawed vertebrates. We previously described the biochemical properties of human AID and found that it is an unusual enzyme in that it exhibits binding affinities for its substrate DNA and catalytic rates several orders of magnitude higher and lower, respectively, than a typical enzyme. Recently, we solved the functional structure of AID and demonstrated that these properties are due to nonspecific DNA binding on its surface, along with a catalytic pocket that predominantly assumes a closed conformation.

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  • Acipenseriformes include sturgeons and paddlefishes, characterized by unique genomic traits like broad ploidy variation and high chromosome numbers, with the American paddlefish showing confirmed palaeotetraploidy.
  • The study revealed that Hox gene paralogs in the paddlefish are distinguishable on chromosomes, with HoxA paralogs clearly visible while HoxD alpha was not successfully identified.
  • Various chromosomal markers were identified, showing stages of rediploidization from ancestral tetraploidy, indicating complex genetic changes in paddlefish evolution.
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We have developed an efficient method for the preparation and maintenance of primary cell cultures isolated from adult , a lobate ctenophore. Our primary cell cultures are derived from tissue explants or enzymatically dissociated cells, and maintained in a complex undefined ctenophore mesogleal serum. These methods can be used to isolate, maintain and visually monitor ctenophore cells to assess proliferation, cellular morphology and cell differentiation in future studies.

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Background: Although many algorithms are now available that aim to characterize different classes of structural variation, discovery of balanced rearrangements such as inversions remains an open problem. This is mainly due to the fact that breakpoints of such events typically lie within segmental duplications or common repeats, which reduces the mappability of short reads. The algorithms developed within the 1000 Genomes Project to identify inversions are limited to relatively short inversions, and there are currently no available algorithms to discover large inversions using high throughput sequencing technologies.

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The pelvic fins of male South American lungfish, Lepidosiren paradoxa, are adorned with a distinctive array of filaments, which grow and become highly vascularized during the breeding season. The resemblance between these pelvic fin filaments (PFFs) and external gills of other vertebrates suggested that this gill-like structure was used for physiological gas exchange. It has been proposed that the unique pelvic fin of male L.

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