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BMC Genetics Jan 2019Sexual precocity is a common biological phenomenon in animal species. A large number of precocity individuals were identified in Chinese mitten crab Eriocheir sinensis,...
BACKGROUND
Sexual precocity is a common biological phenomenon in animal species. A large number of precocity individuals were identified in Chinese mitten crab Eriocheir sinensis, which caused huge economic loss annually. However, the underlying genetic basis of precocity in E. sinensis remains unclear to date.
RESULTS
In this study, morphological and histological observation and comparative transcriptome analysis were conducted among different stages of precocious one-year-old and normal two-year-old sexually mature E. sinensis. The expression profiles of the ovary, hepatopancreas, and eyestalk tissues were presented and compared. Genes associated with lipid metabolic process, lipid transport, vitelline membrane formation, vitelline synthesis, and neuropeptide hormone-related genes were upregulated in the ovary, hepatopancreas, and eyestalk of precocious E. sinensis. Our results indicated that the eyestalk was involved in the neuroendocrine system providing neuropeptide hormones that may induce vitellogenesis in the hepatopancreas and further stimulate ovary development. The hepatopancreas is a site for energy storage and vitellogenin synthesis, and it may assist oogenesis through lipid transport in precocious E. sinensis.
CONCLUSION
We provided not only an effective and convenient phenotype measurement method for the identification of potential precocious E. sinensis detection but also valuable genetic resources and novel insights into the molecular mechanism of precocity in E. sinensis. The genetic basis of precocity in E. sinensis is an integrated gene regulatory network of eyestalk, hepatopancreas, and ovary tissues.
Topics: Animals; Biological Transport; Brachyura; Eye; Female; Gene Expression Profiling; Gene Regulatory Networks; Hepatopancreas; Hormones; Lipid Metabolism; Neuropeptides; Ovary; Phenotype
PubMed: 30683050
DOI: 10.1186/s12863-019-0716-1 -
Journal of Innate Immunity 2019The integrated innate immune features of the calcareous egg and its contents are a critical underpinning of the remarkable evolutionary success of the Aves clade.... (Review)
Review
Dynamics of Structural Barriers and Innate Immune Components during Incubation of the Avian Egg: Critical Interplay between Autonomous Embryonic Development and Maternal Anticipation.
The integrated innate immune features of the calcareous egg and its contents are a critical underpinning of the remarkable evolutionary success of the Aves clade. Beginning at the time of laying, the initial protective structures of the egg, i.e., the biomineralized eggshell, egg-white antimicrobial peptides, and vitelline membrane, are rapidly and dramatically altered during embryonic development. The embryo-generated extra-embryonic tissues (chorioallantoic/amniotic membranes, yolk sac, and associated chambers) are all critical to counteract degradation of primary egg defenses during development. With a focus on the chick embryo (Gallus gallus domesticus), this review describes the progressive transformation of egg innate immunity by embryo-generated structures and mechanisms over the 21-day course of egg incubation, and also discusses the critical interplay between autonomous development and maternal anticipation.
Topics: Animals; Antimicrobial Cationic Peptides; Chick Embryo; Chickens; Egg Shell; Embryonic Development; Female; Immunity, Innate; Maternal-Fetal Exchange; Ovum; Pregnancy; Vitelline Membrane
PubMed: 30391943
DOI: 10.1159/000493719 -
Developmental Biology Oct 2018Metazoan eggs have a specialized coat of extracellular matrix that aids in sperm-egg recognition. The coat is rapidly remodeled after fertilization to prevent polyspermy...
Metazoan eggs have a specialized coat of extracellular matrix that aids in sperm-egg recognition. The coat is rapidly remodeled after fertilization to prevent polyspermy and establish a more permanent barrier to protect the developing embryo. In nematodes, this coat is called the vitelline layer, which is remodeled into the outermost layer of a rigid and impermeable eggshell. We have identified three key components of the vitelline layer structural scaffold - PERM-2, PERM-4 and CBD-1, the first such proteins to be described in the nematode C. elegans. CBD-1 tethered PERM-2 and PERM-4 to the nascent vitelline layer via two N-terminal chitin-binding domains. After fertilization, all three proteins redistributed from the zygote surface to the outer eggshell. Depletion of PERM-2 and PERM-4 from the scaffold led to a porous vitelline layer that permitted soluble factors to leak through the eggshell and resulted in embryonic death. In addition to its role in vitelline layer assembly, CBD-1 is also known to anchor a protein complex required for fertilization and egg activation (EGG-1-5/CHS-1/MBK-2). We found the PERM complex and EGG complex to be functionally independent, and structurally organized through distinct domains of CBD-1. CBD-1 is thus a multifaceted regulator that promotes distinct aspects of vitelline layer assembly and egg activation. In sum, our findings characterize the first vitelline layer components in nematodes, and provide a foundation through which to explore both conserved and species-specific strategies used by animals to build protective barriers following fertilization.
Topics: Animals; Caenorhabditis elegans; Caenorhabditis elegans Proteins; Carrier Proteins; Egg Shell; Fertilization; Membrane Glycoproteins; Oogenesis; Ovum; Vitelline Membrane; Zygote
PubMed: 30120927
DOI: 10.1016/j.ydbio.2018.08.005 -
Developmental Biology Apr 2019Tadpole larvae of the ascidian, Halocynthia roretzi, show morphological left-right asymmetry in the brain structures and the orientation of tail bending within the...
Tadpole larvae of the ascidian, Halocynthia roretzi, show morphological left-right asymmetry in the brain structures and the orientation of tail bending within the vitelline membrane. Neurula embryos rotate along the anterior-posterior axis in a counterclockwise direction, and then this rotation stops when the left side of the embryo is oriented downwards. Contact of the left-side epidermis with the vitelline membrane promotes nodal gene expression in the left-side epidermis. This is a novel mechanism in which rotation of whole embryos provides the initial cue for breaking left-right symmetry. Here we show that epidermal monocilia, which appear at the neurula rotation stage, generate the driving force for rotation. A ciliary protein, Arl13b, fused with Venus YFP was used for live imaging of ciliary movements. Although overexpression of wild-type Arl13b fusion protein resulted in aberrant movements of the cilia and abrogation of neurula rotation, mutant Arl13b fusion protein, in which the GTPase and coiled-coil domains were removed, did not affect the normal ciliary movements and neurula rotation. Epidermis cilia moved in a wavy and serpentine way like sperm flagella but not in a rotational way or beating way with effective stroke and recovery stroke. They moved very slowly, at 1/7 Hz, consistent with the low angular velocity of neurula rotation (ca. 43°/min). The tips of most cilia pointed in the opposite direction of embryonic rotation. Similar motility was also observed in Ciona robusta embryos. When embryos were treated with a dynein inhibitor, Ciliobrevin D, both ciliary movements and neurula rotation were abrogated, showing that ciliary movements drive neurula rotation in Halocynthia. The drug also inhibited Ciona neurula rotation. Our observations suggest that the driving force of rotation is generated using the vitelline membrane as a substrate but not by making a water current around the embryo. It is of evolutionary interest that ascidians use ciliary movements to break embryonic left-right symmetry, like in many vertebrates. Meanwhile, ascidian embryos rotate as a whole, similar to embryos of non-vertebrate deuterostomes, such as echinoderm, hemichordate, and amphioxus, while swimming.
Topics: Animals; Body Patterning; Cilia; Dyneins; Embryo, Mammalian; Epidermis; Movement; Recombinant Fusion Proteins; Rotation; Urochordata
PubMed: 30059669
DOI: 10.1016/j.ydbio.2018.07.023 -
Journal of Visualized Experiments : JoVE Jun 2018Embryonic development is traditionally studied from the perspective of biomolecular genetics, but the fundamental importance of mechanics in morphogenesis is becoming...
Embryonic development is traditionally studied from the perspective of biomolecular genetics, but the fundamental importance of mechanics in morphogenesis is becoming increasingly recognized. In particular, the embryonic chick heart and brain tube, which undergo drastic morphological changes as they develop, are among the prime candidates to study the role of physical forces in morphogenesis. Progressive ventral bending and rightward torsion of the tubular embryonic chick brain happen at the earliest stage of organ-level left-right asymmetry in chick embryonic development. The vitelline membrane (VM) constrains the dorsal side of the embryo and has been implicated in providing the force necessary to induce torsion of the developing brain. Here we present a combination of new ex-ovo experiments and physical modeling to identify the mechanics of brain torsion. At Hamburger-Hamilton stage 11, embryos are harvested and cultured ex ovo (in media). The VM is subsequently removed using a pulled capillary tube. By controlling the level of the fluid and subjecting the embryo to a fluid-air interface, the fluid surface tension of the media can be used to replace the mechanical role of the VM. Microsurgery experiments were also performed to alter the position of the heart to find the resultant change in the chirality of brain torsion. Results from this protocol illustrate the fundamental roles of mechanics in driving morphogenesis.
Topics: Animals; Chickens; Embryonic Development; Morphogenesis
PubMed: 29939170
DOI: 10.3791/57150 -
Poultry Science Nov 2018In this study, we aimed to evaluate the effect of canthaxanthin (CX) and iodine (I) on the production of laying hens, on counteracting debilitation of the vitelline...
In this study, we aimed to evaluate the effect of canthaxanthin (CX) and iodine (I) on the production of laying hens, on counteracting debilitation of the vitelline membrane, and on inhibiting Salmonella growth in eggs stored at 30°C. Three hundred hens were reared in cages. Birds were divided into six feeding groups (10 hens × 5 repetitions) that were administered 0, 3 or 6 ppm of CX and 1 or 10 ppm of I with their diets. Laying rate, egg weights, and feed conversion ratios were controlled. The quality of fresh eggs was assessed in wks 25-26, 48-50 and 62-63 of hens lives. An additional batch of eggs was incubated at the temperature of 30°C, and egg quality changes were monitored on days 3, 6 and 9 of storage. Additionally, eggs collected from four experimental groups of hens whose diets had been iodated with 1 or 10 ppm of I and supplemented with 0 or 6 ppm of CX were infected under laboratory conditions with Salmonella, and incubated for 5 and 10 d. The laying rate, egg weights, and feed conversion ratio were significantly improved. Dietary inclusion of CX contributed to a higher resistance of the vitelline membrane of egg yolks, but only for fresh eggs. Vitelline membrane degradation during egg storage at 30°C was significantly counteracted by dietary inclusion of I at a dose of 10 ppm. The same I dose resulted in the complete inhibition of Salmonella growth until day 10 of incubation, but exclusively for eggs collected from 40-week-old hens. Dietary supplementation with 10 ppm of I was found to impart high level of resistance to the vitelline membrane against the growth of Salmonella in case of eggs stored at 30°C; therefore, I was found to be more beneficial by ensuring longer preservation than that of CX. However, dietary supplementation with CX was found to increase the resistance of vitelline membrane in fresh eggs.
Topics: Animal Feed; Animals; Antioxidants; Canthaxanthin; Chickens; Diet; Dietary Supplements; Dose-Response Relationship, Drug; Female; Iodine; Ovum; Poultry Diseases; Salmonella Infections, Animal; Salmonella enteritidis; Salmonella typhimurium; Temperature; Time Factors; Trace Elements; Vitelline Membrane
PubMed: 29931093
DOI: 10.3382/ps/pey264 -
Toxins Jun 2018(class Anthozoa) is a zoantharian which, together with other cnidarians, like jellyfishes, hydra, and sea anemones, possesses specialized structures in its tissues, the...
(class Anthozoa) is a zoantharian which, together with other cnidarians, like jellyfishes, hydra, and sea anemones, possesses specialized structures in its tissues, the cnidocytes, which deliver an array of toxins in order to capture prey and deter predators. The whole transcriptome of was deep sequenced, and a diversity of toxin-related peptide sequences were identified, and some retrieved for functional analysis. In this work, a peptide precursor containing a ShK domain, named PcShK3, was analyzed by means of computational processing, comprising structural phylogenetic analysis, model prediction, and dynamics simulation of peptide-receptor interaction. The combined data indicated that PcShK3 is a distinct peptide which is homologous to a cluster of peptides belonging to the ShK toxin family. In vivo, PcShK3 distributed across the vitelline membrane and accumulated in the yolk sac stripe of zebrafish larvae. Notably, it displayed a significant cardio-protective effect in zebrafish in concentrations inferior to the IC (<43.53 ± 6.45 µM), while in high concentrations (>IC), it accumulated in the blood and caused pericardial edema, being cardiotoxic to zebrafish larvae. Remarkably, PcShK3 suppressed the 6-OHDA-induced neurotoxicity on the locomotive behavior of zebrafish. The present results indicated that PcShK3 is a novel member of ShK toxin family, and has the intrinsic ability to induce neuro- and cardio-protective effects or cause cardiac toxicity, according to its effective concentration.
Topics: Animals; Animals, Genetically Modified; Anthozoa; Behavior, Animal; Cardiotonic Agents; Cnidarian Venoms; Dose-Response Relationship, Drug; Heart; Neuroprotective Agents; Oxidopamine; Peptides; Transcriptome; Zebrafish
PubMed: 29895785
DOI: 10.3390/toxins10060238 -
PLoS Neglected Tropical Diseases Apr 2018Clonorchis sinensis is a liver fluke that can dwell in the bile ducts of mammals. Bile acid transporters function to maintain the homeostasis of bile acids in C....
Clonorchis sinensis is a liver fluke that can dwell in the bile ducts of mammals. Bile acid transporters function to maintain the homeostasis of bile acids in C. sinensis, as they induce physiological changes or have harmful effects on C. sinensis survival. The organic solute transporter (OST) transports mainly bile acid and belongs to the SLC51 subfamily of solute carrier transporters. OST plays a critical role in the recirculation of bile acids in higher animals. In this study, we cloned full-length cDNA of the 480-amino acid OST from C. sinensis (CsOST). Genomic analysis revealed 11 exons and nine introns. The CsOST protein had a 'Solute_trans_a' domain with 67% homology to Schistosoma japonicum OST. For further analysis, the CsOST protein sequence was split into the ordered domain (CsOST-N) at the N-terminus and disordered domain (CsOST-C) at the C-terminus. The tertiary structure of each domain was built using a threading-based method and determined by manual comparison. In a phylogenetic tree, the CsOST-N domain belonged to the OSTα and CsOST-C to the OSTβ clade. These two domains were more highly conserved with the OST α- and β-subunits at the structure level than at sequence level. These findings suggested that CsOST comprised the OST α- and β-subunits. CsOST was localized in the oral and ventral suckers and in the mesenchymal tissues abundant around the intestine, vitelline glands, uterus, and testes. This study provides fundamental data for the further understanding of homologues in other flukes.
Topics: Amino Acid Sequence; Animals; Bile Acids and Salts; Biological Transport; Carrier Proteins; Clonorchiasis; Clonorchis sinensis; Female; Helminth Proteins; Membrane Glycoproteins; Mice, Inbred BALB C; Models, Molecular; Phylogeny; Protein Transport; Recombinant Proteins; Sequence Alignment
PubMed: 29702646
DOI: 10.1371/journal.pntd.0006459 -
The International Journal of... 2018This paper provides a brief account of some aspects of the career of Ruth Bellairs using selected examples from her research publications, with the emphasis being placed...
This paper provides a brief account of some aspects of the career of Ruth Bellairs using selected examples from her research publications, with the emphasis being placed on the early stages of chick embryo development, and in particular, on cell migration. Topics include the role of Hensen's node, the vitelline membrane, the structure and segmentation of somites, the tail bud and the Wolffian duct. Her research approach has involved embryo culture, experimental surgery, transmission and scanning electron microscopy, time-lapse filming and immunostaining techniques.
Topics: Animals; Cell Movement; Chick Embryo; Chickens; Embryo Culture Techniques; Embryology; Embryonic Induction; England; History, 20th Century; History, 21st Century; Mesoderm; Microscopy, Electron, Scanning; Microscopy, Electron, Transmission; Organizers, Embryonic
PubMed: 29616723
DOI: 10.1387/ijdb.180028rb -
Molecular & Cellular Proteomics : MCP Mar 2019In many amniotes, the amniotic fluid is depicted as a dynamic milieu that participates in the protection of the embryo (cushioning, hydration, and immunity). However, in...
In many amniotes, the amniotic fluid is depicted as a dynamic milieu that participates in the protection of the embryo (cushioning, hydration, and immunity). However, in birds, the protein profile of the amniotic fluid remains unexplored, even though its proteomic signature is predicted to differ compared with that of humans. In fact, unlike humans, chicken amniotic fluid does not collect excretory products and its protein composition strikingly changes at mid-development because of the massive inflow of egg white proteins, which are thereafter swallowed by the embryo to support its growth. Using GeLC-MS/MS and shotgun strategies, we identified 91 nonredundant proteins delineating the chicken amniotic fluid proteome at day 11 of development, before egg white transfer. These proteins were essentially associated with the metabolism of nutrients, immune response and developmental processes. Forty-eight proteins were common to both chicken and human amniotic fluids, including serum albumin, apolipoprotein A1 and alpha-fetoprotein. We further investigated the effective role of chicken amniotic fluid in innate defense and revealed that it exhibits significant antibacterial activity at day 11 of development. This antibacterial potential is drastically enhanced after egg white transfer, presumably due to lysozyme, avian beta-defensin 11, vitelline membrane outer layer protein 1, and beta-microseminoprotein-like as the most likely antibacterial candidates. Interestingly, several proteins recovered in the chicken amniotic fluid prior and after egg white transfer are uniquely found in birds (ovalbumin and related proteins X and Y, avian beta-defensin 11) or oviparous species (vitellogenins 1 and 2, riboflavin-binding protein). This study provides an integrative overview of the chicken amniotic fluid proteome and opens stimulating perspectives in deciphering the role of avian egg-specific proteins in embryonic development, including innate immunity. These proteins may constitute valuable biomarkers for poultry production to detect hazardous situations (stress, infection, etc.), that may negatively affect the development of the chicken embryo.
Topics: Amniotic Fluid; Animals; Anti-Bacterial Agents; Avian Proteins; Chickens; Egg White; Embryonic Development; Evolution, Molecular; Gene Ontology; Phylogeny; Proteome; Proteomics
PubMed: 29444982
DOI: 10.1074/mcp.RA117.000459