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1.
Dev Genes Evol ; 230(1): 39-45, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31960123

RESUMO

The molluscan larval shell formation is a complicated process. There is evidence that the mantle of the primary larva (trochophore) contains functionally different cell populations with distinct gene expression profiles. However, it remains unclear how these cells are specified. In the present study, we identified three cell populations from the shell gland in earlier stages (gastrula) from the bivalve mollusc Crassostrea gigas. These cell populations were determined by analyzing the co-expression relationships among six potential shell formation (pSF) genes using two-color hybridization. The three cell populations, which we designated as SGCPs (shell gland cell populations), formed a concentric-circle pattern from outside to inside of the shell gland. SGCP I was located in the outer edge of the shell gland and the cells expressed pax2/5/8, gata2/3, and bmp2/4. SGCP II was located more internally and the cells expressed two engrailed genes. The last population, SGCP III, was located in the central region of the shell gland and the cells expressed lox4. Determination of the gene expression profiles of SGCPs would help trace their origins and fates and elucidate how these cell populations are specified. Moreover, potential roles of the SGCPs, e.g., development of sensory cells and shell biogenesis, are suggested. Our results reveal the internal organization of the embryonic shell gland at the molecular level and add to the knowledge of larval shell formation.


Assuntos
Crassostrea/citologia , Exoesqueleto/citologia , Exoesqueleto/metabolismo , Animais , Crassostrea/genética , Crassostrea/crescimento & desenvolvimento , Crassostrea/metabolismo , Glândulas Exócrinas/citologia , Glândulas Exócrinas/metabolismo , Feminino , Masculino , Fatores de Transcrição/metabolismo
2.
Food Chem ; 310: 125819, 2020 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-31732248

RESUMO

The well-known red color change plays a significant role in consumer acceptability of crustacean species. In this study, we described the purification of the red color-related protein named MjRCP75 from the shell of Marsupenaeus japonicus. It was a homogeneous monomer with molecular mass of 75 kDa and rich in α-helix conformation. The α-helix content decreased within the increasing of heating temperature and was transformed dominantly to ß types. Identification and structural analysis revealed that MjRCP75 belonged to hemocyanin family. The released pigment from heated MjRCP75 showed a λmax at 483 nm in acetone. MjRCP75 showed clearly antibacterial activity against Escherichia coli, Staphylococcus aureus, and Vibrio parahaemolyticus. These findings identify MjRCP75 as the red color-related protein in M. japonicus shell and reveal its involvement in antibacterial activities.


Assuntos
Exoesqueleto/química , Antibacterianos/farmacologia , Proteínas de Artrópodes/química , Proteínas de Artrópodes/farmacologia , Penaeidae/química , Animais , Antibacterianos/química , Proteínas de Artrópodes/isolamento & purificação , Avaliação Pré-Clínica de Medicamentos , Escherichia coli/efeitos dos fármacos , Hemocianinas/química , Testes de Sensibilidade Microbiana , Peso Molecular , Pigmentos Biológicos/química , Conformação Proteica , Staphylococcus aureus/efeitos dos fármacos , Vibrio parahaemolyticus/efeitos dos fármacos
3.
Insect Biochem Mol Biol ; 117: 103291, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31812474

RESUMO

In many arthropod species including insects, the cuticle tanning pathway for both pigmentation and sclerotization begins with tyrosine and is responsible for production of both melanin- and quinoid-type pigments, some of which are major pigments for body coloration. In this study we identified and cloned cDNAs of the yellow mealworm, Tenebrio molitor, encoding seven key enzymes involved in this pathway including tyrosine hydroxylase (TmTH), DOPA decarboxylase (TmDDC), laccase 2 (TmLac2), Yellow-y (TmY-y), arylalkylamine N-acetyltransferase (TmAANAT1), aspartate 1-decarboxylase (TmADC) and N-ß-alanyldopamine synthase (Tmebony). Expression profiles of these genes during development were analyzed by real-time PCR, revealing development-specific patterns of expression. Loss of function mediated by RNAi of either 1) TmTH or TmLac2, 2) TmDDC or TmY-y, and 3) TmAANAT1, TmADC or Tmebony resulted in pale/white, light yellow/brown and dark/black adult body coloration, respectively. In addition, there are three distinct layer/regional pigmentation differences in rigid types of adult cuticle, a brownish outer exocuticle (EX), a dark pigmented middle mesocuticle (ME) and a transparent inner endocuticle (EN). Decreases in pigmentation of the EX and/or ME layers were observed after RNAi of TmDDC or TmY-y. In TmADC- or Tmebony-deficient adults, a darker pigmented EX layer was observed. In TmAANAT1-deficient adults, trabeculae formed between the dorsal and ventral elytral cuticles as well as the transparent EN layer became highly pigmented. These results demonstrate that knocking down the level of gene expression of specific enzymes of this tyrosine metabolic pathway leads to abnormal pigmentation in individual layers and substructure of the rigid adult exoskeleton of T. molitor.


Assuntos
Proteínas de Insetos/genética , Pigmentação/genética , Tenebrio/fisiologia , Exoesqueleto/fisiologia , Animais , Proteínas de Insetos/metabolismo , Tenebrio/genética , Asas de Animais/fisiologia
4.
Food Chem ; 302: 125334, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31419773

RESUMO

Carotenoids, natural pigments, are a group of chemically heterogeneous molecules, present in numerous taxonomical clusters. Because of their various bioactivities, carotenoids are day-by-day applied in numerous fields. The present work aimed to investigate an efficient extraction process of carotenoids from blue crab shells and their identification by HR-ESI-MS technique. In this context, different methods (enzymatic, maceration, Soxhlet, etc.) and solvents (variable polarity index) were tested. Maceration using the binary system hexane/isopropanol (50/50) was found to be the most efficient process, producing high carotenoids content and low total phenolic and soluble protein amounts (p < 0.05). When combined with an enzymatic pretreatment, this procedure was found to be remarkably (p < 0.05) more efficient and selective especially towards astaxanthin (p < 0.05). The HR-ESI-MS identified 23 compounds, depending on the adopted extraction approach. The compounds identified may have potential for applications in food or pharmaceutical industries.


Assuntos
Exoesqueleto/química , Braquiúros/química , Carotenoides/isolamento & purificação , Fracionamento Químico/métodos , 2-Propanol/química , Animais , Carotenoides/análise , Hexanos/química , Fenóis/análise , Fenóis/química , Proteínas/análise , Proteínas/isolamento & purificação , Solventes/química , Espectrometria de Massas por Ionização por Electrospray , Espectroscopia de Infravermelho com Transformada de Fourier , Xantofilas/análise , Xantofilas/isolamento & purificação
5.
Zoolog Sci ; 36(6): 468-470, 2019 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-31833317

RESUMO

This study describes shell-exchange behavior in the hermit-crab-like tanaidacean Macrolabrum sp. (Pagurapseudidae: Pagurapseudinae) under captive conditions. I observed one shell exchange by Macrolabrum sp., the behavioral sequence of which was as follows: a shell-carrying tanaidacean 1) grasped the edge of the aperture of an empty gastropod shell with its right cheliped; 2) inspected the condition inside the shell four times by inserting the anterior portion of its body into the shell; and 3) moved into the shell, posterior end (pleotelson) first. The elapsed time from the initial grasping of the empty shell to completing the move into it was 2 min 20 sec. In contrast to a Pagurapseudes tanaidacean and hermit crabs, the individual of Macrolabrum sp. did not examine the external surface of the shell during the single shell exchange observed.


Assuntos
Exoesqueleto , Comportamento Animal , Crustáceos/fisiologia , Animais
6.
Biofouling ; 35(8): 945-957, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31687858

RESUMO

Ocean uptake of anthropogenic CO2 causes ocean acidification (OA), which not only decreases the calcification rate, but also impairs the formation of calcareous shells or tubes in marine invertebrates such as the dominant biofouling tubeworm species, Hydroides elegans. This study examined the ability of tubeworms to resume normal tube calcification when returned to ambient pH 8.1 from a projected near-future OA level of pH 7.8. Tubeworms produced structurally impaired and mechanically weaker calcareous tubes at pH 7.8 compared to at pH 8.1, but were able to recover when the pH was restored to ambient levels. This suggests that tubeworms can physiologically recover from the impacts of OA on tube calcification, composition, density, hardness and stiffness when returned to optimal conditions. These results help understanding of the progression of biofouling communities dominated by tubeworms in future oceans with low pH induced by OA.


Assuntos
Organismos Aquáticos/efeitos dos fármacos , Incrustação Biológica , Calcificação Fisiológica/efeitos dos fármacos , Poliquetos/efeitos dos fármacos , Água do Mar/química , Ácidos , Exoesqueleto/química , Exoesqueleto/efeitos dos fármacos , Animais , Organismos Aquáticos/fisiologia , Incrustação Biológica/prevenção & controle , Dióxido de Carbono/toxicidade , Previsões , Concentração de Íons de Hidrogênio , Oceanos e Mares , Poliquetos/fisiologia , Poluentes Químicos da Água/toxicidade
7.
BMC Evol Biol ; 19(1): 210, 2019 11 13.
Artigo em Inglês | MEDLINE | ID: mdl-31722660

RESUMO

BACKGROUND: Many pathologies that modify the shell geometry and ornamentation of ammonoids are known from the fossil record. Since they may reflect the developmental response of the organism to a perturbation (usually a sublethal injury), their study is essential for exploring the developmental mechanisms of these extinct animals. Ammonoid pathologies are also useful to assess the value of some morphological characters used in taxonomy, as well as to improve phylogenetic reconstructions and evolutionary scenarios. RESULTS: We report on the discovery of an enigmatic pathological middle Toarcian (Lower Jurassic) ammonoid specimen from southern France, characterized by a pronounced left-right asymmetry in both ornamentation and suture lines. For each side independently, the taxonomic interpretations of ornamentation and suture lines are congruent, suggesting a Hildoceras semipolitum species assignment for the left side and a Brodieia primaria species assignment for the right side. The former exhibits a lateral groove whereas the second displays sinuous ribs. This specimen, together with the few analogous cases reported in the literature, lead us to erect a new forma-type pathology herein called "forma janusa" for specimens displaying a left-right asymmetry in the absence of any clear evidence of injury or parasitism, whereby the two sides match with the regular morphology of two distinct, known species. CONCLUSIONS: Since "forma janusa" specimens reflect the underlying developmental plasticity of the ammonoid taxa, we hypothesize that such specimens may also indicate unsuspected phylogenetic closeness between the two displayed taxa and may even reveal a direct ancestor-descendant relationship. This hypothesis is not, as yet, contradicted by the stratigraphical data at hand: in all studied cases the two distinct taxa correspond to contemporaneous or sub-contemporaneous taxa. More generally, the newly described specimen suggests that a hitherto unidentified developmental link may exist between sinuous ribs and lateral grooves. Overall, we recommend an integrative approach for revisiting aberrant individuals that illustrate the intricate links among shell morphogenesis, developmental plasticity and phylogeny.


Assuntos
Exoesqueleto/anatomia & histologia , Cefalópodes/anatomia & histologia , Fósseis , Animais , Evolução Biológica , Cefalópodes/classificação , França , Morfogênese , Filogenia
8.
Zootaxa ; 4624(4): zootaxa.4624.4.5, 2019 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-31716199

RESUMO

Actinopus specimens from different localities in Uruguay that did not match any of the previously species present in the country were examined, and four new species are described: A. coboi sp. nov., from Colonia province; A. fernandezi sp. nov., from Salto province; A. simoi sp. nov., from Maldonado province; and A. uruguayense sp. nov., from Colonia and Cerro Largo provinces. The record of the species A. longipalpis for Montevideo is rejected and A. liodon is considered "species inquirenda". Actinopus coboi has spermathecae with an apical lobe diagonally directed; A. fernandezi is characterized by a stylized copulatory bulb and its greater number of retrolateral thorns on tibia II. Actinopus simoi can be distinguished from A. uruguayense by its carapace with a dark coloration; a reddish coloration in the palpal tibia and the shape of its spermathecae and copulatory bulb. With the presence of the Argentinian species-A. gerschiapelliarum, A. puelche and A. insignis-the number of species known in the country is increased to nine. All new species are diagnosed and illustrated; a dichotomous key to all species of Actinopus from Uruguay is also provided.


Assuntos
Aranhas , Distribuição Animal , Exoesqueleto , Animais , Raízes de Plantas , Uruguai
9.
Zootaxa ; 4560(2): zootaxa.4560.2.1, 2019 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-31716578

RESUMO

The genus Leiogalathea Baba, 1969 currently contains only two benthic species both occurring on the continental shelves and slope: L. laevirostris (Balss, 1913), widely reported in the Indo-Pacific region, and L. agassizii (A. Milne Edwards, 1880), from both sides of the Central Atlantic. A certain degree of morphological variability linked to their geographic distributions was previously noticed, mostly in L. laevirostris. In the present study, we revise numerous specimens collected from the Atlantic, Indian and Pacific Oceans, analysing morphological and molecular characters (COI and 16S rRNA). We found 15 new species; all of them are distinguished from L. laevirostris and L. agassizii by subtle but constant morphological differences and show clear genetic separation. Furthermore, L. imperialis (Miyake Baba, 1967), previously synonymized with L. laevirostris, was found to be a valid species. All species are described and illustrated. Species of the genus Leiogalathea are morphologically distinguishable on the basis of the spinulation of the carapace, the shape and the armature of the rostrum, the shape of the propodi of the walking legs, and the pattern of the setae covering on rostrum, carapace and chelae. Some species are barely discernible on the basis of these characters but are highly divergent genetically.


Assuntos
Anomuros , Exoesqueleto , Animais , Oceano Pacífico , RNA Ribossômico 16S
10.
Anim Genet ; 50(6): 733-739, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31571283

RESUMO

Integrated linkage maps for each sex have been constructed for the Pacific abalone Haliotis discus hannai using three F1 mapping families based on co-dominant markers. A total of 273 markers were placed on the female map, spanning 927.3 cM with an average interval of 3.64 cM, whereas 277 markers were mapped on the male map, covering 727.0 cM with an average spacing of 2.80 cM. Both female and male maps consisted of 18 linkage groups, corresponding well with the number of chromosomes. Furthermore, the sex-determining locus and the green/orange shell color controlling locus were mapped to the linkage group 3 (LG3) and LG9 respectively. A marker completely linked to phenotypic sex was identified, and the sex determination system was further concluded as paternal heterogametic (males XY and females XX). Based on the segregation ratio of the shell color in the progeny, a simple recessive model of epistasis was proposed to explain the distribution of different color morphs (green, orange and blue): the recessive allele determining orange type masks the effect of the locus controlling green and blue types, whereas the dominant allele at the green/orange locus permits the expression of green and blue types controlled by another locus. The current consensus map provides a useful framework for genetic studies in the Pacific abalone. Mapping of the sex-determining locus and the shell color-controlling locus leads to further understanding of the mechanisms underlying these important traits.


Assuntos
Gastrópodes/genética , Gastrópodes/fisiologia , Exoesqueleto , Animais , Feminino , Masculino , Repetições de Microssatélites , Pigmentação , Polimorfismo de Nucleotídeo Único , Processos de Determinação Sexual
11.
Zool Res ; 40(6): 541-551, 2019 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-31502425

RESUMO

The systematics of Semisulcospiridae in China is revised here based on morphological characters and mitochondrial phylogenetics. Phylogenetic relationships within the Chinese semisulcospirids were assessed via DNA sequences from mitochondrial analysis (cytochrome c oxidase I and 16S rRNA). This research contains most morphospecies of semisulcospirids previously recorded in China. Based on these results, the family of Chinese Semisulcospiridae is represented by three genera: i.e., viviparous Semisulcospira Böttger, 1886, oviparous Hua Chen, 1943 and Koreoleptoxis Burch and Jung, 1988. These genera can be distinguished from each other by reproductive anatomy, reproductive mode, and radula features. Species of Hua are mainly distributed in southwest China and Guangxi, whereas Koreoleptoxis and Semisulcospira are mainly distributed in south and northeast China.


Assuntos
DNA Mitocondrial/genética , Gastrópodes/genética , Variação Genética , Filogenia , Exoesqueleto/anatomia & histologia , Animais , China , Gastrópodes/anatomia & histologia , Genômica , Especificidade da Espécie
12.
Isotopes Environ Health Stud ; 55(6): 511-525, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31533477

RESUMO

Freshwater bivalve shell oxygen isotope values (δ18OS) may act as a recorder of river δ18O variations that can then be interpreted in terms of hydrology (e.g. precipitation-evaporation balance, precipitation and river discharge patterns). We investigated the potential of this proxy measured across the hinge of South American unionid shells: Anodontites elongatus collected in Peru and A. trapesialis in Brazil. The isotopic signatures were reproducible between individuals of the same species. A. trapesialis clearly showed a strong δ18OS cyclicity in accordance with its growth patterns while A. elongatus presented less clear δ18OS with lower amplitude. We confirm that the deposition of successive growth lines and increments is annual, with growth line corresponding to the wet season. Also, we suggest that low amplitude of δ18OS in the A. elongatus shells indicates a habitat close to the river while large amplitude of δ18OS cycles observed in A. trapesialis shells would reflect a floodplain lake habitat, seasonally disconnected from the river and thus subjected to higher seasonal fluctuations in water δ18O. Considering these promising first results, future studies could be directed towards the use of fossil shells to reconstruct the past and present hydrological and geochemical conditions of the Amazon.


Assuntos
Exoesqueleto/química , Bivalves/química , Monitoramento Ambiental/métodos , Isótopos de Oxigênio/análise , Rios/química , Ciclo Hidrológico , Animais , Brasil , Lagos/química , Estações do Ano
13.
Sci Total Environ ; 692: 833-843, 2019 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-31539989

RESUMO

Ocean acidification is mainly being monitored using data loggers which currently offer limited coverage of marine ecosystems. Here, we trial the use of gastropod shells to monitor acidification on rocky shores. Animals living in areas with highly variable pH (8.6-5.9) were compared with those from sites with more stable pH (8.6-7.9). Differences in site pH were reflected in size, shape and erosion patterns in Nerita chamaeleon and Planaxis sulcatus. Shells from acidified sites were shorter, more globular and more eroded, with both of these species proving to be good biomonitors. After an assessment of baseline weathering, shell erosion can be used to indicate the level of exposure of organisms to corrosive water, providing a tool for biomonitoring acidification in heterogeneous intertidal systems. A shell erosion ranking system was found to clearly discriminate between acidified and reference sites. Being spatially-extensive, this approach can identify coastal areas of greater or lesser acidification. Cost-effective and simple shell erosion ranking is amenable to citizen science projects and could serve as an early-warning-signal for natural or anthropogenic acidification of coastal waters.


Assuntos
Exoesqueleto/anatomia & histologia , Gastrópodes/anatomia & histologia , Água do Mar/química , Exoesqueleto/efeitos dos fármacos , Animais , Brunei , Gastrópodes/efeitos dos fármacos , Concentração de Íons de Hidrogênio , Especificidade da Espécie
14.
Mater Sci Eng C Mater Biol Appl ; 105: 110102, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31546340

RESUMO

The Hydroxyapatite (HA, Ca10(PO4)6(OH)2) has attracted widely research interests in many aspects, especially in repairing and replacing human hard tissues due to its brilliant biocompatibility, biological activity and so on. In the present article, HA nano-rods were rapidly developed via hydrothermal reaction synthesized with two representative surfactants (hexadecyltrimethylammonium bromide and sodium dodecyl sulfate) taken oyster shells as raw materials. The scanning electron microscopy (SEM) observations demonstrated that the micromorphology of synthesized HA was constructed of relatively regular nano-rods. From the zeta potential (ZP) analysis, the zeta potential of the developed HA was affected by different surfactants, which demonstrated the opposite potential value. The Fourier transform infrared spectroscopy (FT-IR) and X-ray diffraction (XRD) results showed the HA phase was successfully and rapidly developed on the surface of oyster shell with the help of surfactants. The bio-safety of HA nano-rods was confirmed by MTT cytotoxicity assay using pre-osteoblasts cells. A possible hard-template transformation mechanism from the calcite and aragonite phases into the HA phase was proposed.


Assuntos
Exoesqueleto/química , Crassostrea/química , Durapatita , Nanotubos/química , Osteoblastos/metabolismo , Tensoativos , Animais , Linhagem Celular , Durapatita/química , Durapatita/farmacologia , Camundongos , Osteoblastos/citologia , Tensoativos/química , Tensoativos/farmacologia
15.
Molecules ; 24(18)2019 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-31546939

RESUMO

Scallop-shell powder (SSP) heated at high temperature exhibits high pH and broad antimicrobial activity. Bioshell calcium oxide (BiSCaO) is an SSP composed mainly of calcium oxide. It is poorly water-soluble under alkaline conditions and the generated precipitate can plug spray nozzles. The aim of this study was to establish that BiSCaO dispersion caused no significant CaO loss and plugging of spray nozzles, and to evaluate its deodorization and microbicidal abilities and its ability to reduce the concentrations of NO2- and NO3-. BiSCaO dispersions were prepared by mixing various concentrations of BiSCaO suspension, while phosphate compounds such as Na3PO4, Na2HPO4 or NaH2PO4 and the pH, average diameter, zeta potential, and form of the compounds with cryo-SEM were evaluated. We evaluated deodorization using tainted pork meat and microbicidal efficacy using contaminated suspension with normal bacterial flora. The concentration of NO2- and NO3- after mixing BiSCaO dispersion and pure water containing a high proportion of NO2- and NO3- were measured. BiSCaO dispersion formed with Na2HPO4, whose ratio to BiSCaO was 60%, showed a high pH (>12), a small particle diameter (>181 nm) and was stable for seven days. The BiSCaO dispersion showed higher deodorization and microbicidal activities than SSP-Ca(OH)2, which was mainly composed of Ca(OH)2. BiSCaO, but not SSP-Ca(OH)2, could reduce the concentration of NO2- and NO3- by more than 90% within 15 min. We developed a stable BiSCaO dispersion, and it had high deodorization and microbicidal efficacy. These activities of BiSCaO might result from the high pH caused by CaO hydration and a reduction activity causing active radical species.


Assuntos
Exoesqueleto/química , Antibacterianos/farmacologia , Compostos de Cálcio/farmacologia , Nanopartículas/química , Óxidos/farmacologia , Animais , Nanopartículas/ultraestrutura , Nitratos/análise , Nitritos/análise , Tamanho da Partícula , Pectinidae/química , Ácidos Fosfóricos/química , Suspensões , Suínos
16.
Mar Biotechnol (NY) ; 21(5): 683-696, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31385168

RESUMO

The molecular mechanisms of shell formation and pigmentation are issues of great interest in molluscan studies due to the unique physical and biological properties of shells. The Yesso scallop, Patinopecten yessoensis, is one of the most important maricultural bivalves in Asian countries, and its shell color shows polymorphism. To gain more information about the underlying mechanisms of shell formation and pigmentation, this study presents the first analyses of histological and transcriptional differences between different mantle regions of the Yesso scallop, which are thought to be responsible for the formation of different shell layers. The results showed major microstructural differences between the edge and central mantles, which were closely associated with their functions. Different biomineralization-related GO functions, which might participate in the formation of different shell layers, were significantly enriched in the different mantle regions, indicating the different molecular functions of the two mantle regions in shell formation. The melanogenesis pathway, which controls melanin biosynthesis, was the most significantly enriched pathway in the DEGs between the two mantle regions, indicating its important role in shell pigmentation. Tyr, the key and rate-limiting gene in melanogenesis, was expressed at a remarkably high level in the central mantle, while the upstream regulatory genes included in melanogenesis were mainly upregulated in the edge mantle, suggesting the different molecular functions of the two mantle regions in shell pigmentation.


Assuntos
Exoesqueleto/metabolismo , Calcificação Fisiológica/genética , Pectinidae/genética , Pigmentação/genética , Proteínas/genética , Transcriptoma , Exoesqueleto/anatomia & histologia , Animais , Cor , Perfilação da Expressão Gênica , Ontologia Genética , Melaninas/biossíntese , Melaninas/genética , Anotação de Sequência Molecular , Pectinidae/classificação , Pectinidae/crescimento & desenvolvimento , Pectinidae/metabolismo , Filogenia , Proteínas/classificação , Proteínas/metabolismo
17.
Glob Chang Biol ; 25(12): 4179-4193, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31432587

RESUMO

Although geographical patterns of species' sensitivity to environmental changes are defined by interacting multiple stressors, little is known about compensatory processes shaping regional differences in organismal vulnerability. Here, we examine large-scale spatial variations in biomineralization under heterogeneous environmental gradients of temperature, salinity and food availability across a 30° latitudinal range (3,334 km), to test whether plasticity in calcareous shell production and composition, from juveniles to large adults, mediates geographical patterns of resilience to climate change in critical foundation species, the mussels Mytilus edulis and M. trossulus. We find shell calcification decreased towards high latitude, with mussels producing thinner shells with a higher organic content in polar than temperate regions. Salinity was the best predictor of within-region differences in mussel shell deposition, mineral and organic composition. In polar, subpolar, and Baltic low-salinity environments, mussels produced thin shells with a thicker external organic layer (periostracum), and an increased proportion of calcite (prismatic layer, as opposed to aragonite) and organic matrix, providing potentially higher resistance against dissolution in more corrosive waters. Conversely, in temperate, higher salinity regimes, thicker, more calcified shells with a higher aragonite (nacreous layer) proportion were deposited, which suggests enhanced protection under increased predation pressure. Interacting effects of salinity and food availability on mussel shell composition predict the deposition of a thicker periostracum and organic-enriched prismatic layer under forecasted future environmental conditions, suggesting a capacity for increased protection of high-latitude populations from ocean acidification. These findings support biomineralization plasticity as a potentially advantageous compensatory mechanism conferring Mytilus species a protective capacity for quantitative and qualitative trade-offs in shell deposition as a response to regional alterations of abiotic and biotic conditions in future environments. Our work illustrates that compensatory mechanisms, driving plastic responses to the spatial structure of multiple stressors, can define geographical patterns of unanticipated species resilience to global environmental change.


Assuntos
Biomineralização , Mytilus edulis , Exoesqueleto , Animais , Concentração de Íons de Hidrogênio , Água do Mar
18.
J Mater Sci Mater Med ; 30(9): 100, 2019 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-31468139

RESUMO

Nacre (mother of pearl) is a natural biomaterial used to prepare orthopedic devices. We have implanted screws and plates made with nacre in five sheeps. Bone were harvested after two months and embedded in poly(methyl methacrylate). Blocks were saws and the thick slabs were grinded, polished and surface stained. Sections were photographed at an ×1000 magnification. Giant cells were found in contact with nacre in eroded areas and true osteoclasts were found at distance in the neighboring bone in Howship lacunae. A texture analysis of the nuclei of giant cells and osteoclasts was done using the run-length method of the MaZda freeware. The size of the nuclei was reduced in osteoclast and their mean gray level appeared reduced. Texture analysis revealed that chromatin had a completely different pattern in giant cells when compared to osteoclasts. Giant cells had a fine repartition of the chromatin with large clear areas around prominent nucleoli. On the contrary, osteoclast nuclei had chromatin blocks evenly dispersed in the nuclei. This reflects the different origin of these cells expressing different functions.


Assuntos
Substitutos Ósseos/análise , Transplante Ósseo , Células Gigantes/patologia , Técnicas Histológicas/métodos , Nácar , Osteoclastos/patologia , Exoesqueleto/química , Animais , Transplante Ósseo/instrumentação , Transplante Ósseo/métodos , Prótese Ancorada no Osso , Núcleo Celular/química , Reação a Corpo Estranho/patologia , Citometria por Imagem/métodos , Nácar/química , Pinctada , Ovinos
19.
Mar Pollut Bull ; 146: 236-246, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31426152

RESUMO

Bivalves facilitate microbial nitrogen cycling, which can produce nitrous oxide (N2O), a potent greenhouse gas. Potential N2O production by three marine bivalves (Mytilus edulis, Mercenaria mercenaria and Crassostrea virginica) was measured in the laboratory including responses to nitrogen (N) loading and/or warming over short-terms (up to 14 or 28 days). N additions (targeting 100 µM-N ammonium nitrate) or warming (22 °C) individually and in combination were applied with experimental controls (20 µM-N, 19 °C). N2O production rates were higher with N additions for all species, but warming lacked significant direct effects. Ammonium and nitrate concentrations varied but were consistent with nitrification as a potential N2O source for all bivalves. Highest N2O emissions (7.5 nmol N2O g-1 h-1) were from M. edulis under hypoxic conditions coincident with a drop in pH. Macro-epifauna on M. edulis did not significantly alter N2O production. Thus, under short-term hypoxic conditions, micro-organisms in M. edulis guts may be a particularly significant source of N2O.


Assuntos
Crassostrea/metabolismo , Mercenaria/metabolismo , Mytilus edulis/metabolismo , Óxido Nitroso/metabolismo , Compostos de Amônio/metabolismo , Exoesqueleto/fisiologia , Animais , Crassostrea/fisiologia , Concentração de Íons de Hidrogênio , Mercenaria/fisiologia , Mytilus edulis/fisiologia , Nitratos/metabolismo , Nitrificação , Ciclo do Nitrogênio , Nutrientes/metabolismo , Rhode Island , Água do Mar/química , Temperatura Ambiente , Qualidade da Água
20.
Mar Biotechnol (NY) ; 21(5): 634-642, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31267359

RESUMO

The nacre color of shells has an effect on the pearl color in Hyriopsis cumingii and is an important indicator for its value. The nacre is part of the shell, and some studies have shown that exosomes of the mantle are involved in the formation of shells. Most of the RNA contained in exosomes are microRNAs (miRNAs); however, little information is available on the roles of exosomes and miRNAs on the formation of nacre color in mussels. In this study, exosomes of mantles were extracted from white and purple mussels. High-throughput Illumina sequencing was performed on the white and purple mussel mantle exosomes, and 7,665,167 and 10,994,115 reads were harvested. Using the standard of |log2(Fold change)| ≥ 2, and a p value ≤ 0.05, a total of 54 differentially expressed miRNAs were identified. The miRNAs that regulated the target genes (hcApo, HcTyr, HcTyp-1, HcMitf, HcSRCR1, and HcSRCR2) involved in shell color formation were predicted. Moreover, miR-15b negatively regulated hcApo, which plays important roles in the absorption and transport of ß-carotene in H. cumingii. These results improve our understanding of the molecular mechanisms of nacre color formation in H. cumingii.


Assuntos
Exoesqueleto/metabolismo , Exossomos/metabolismo , MicroRNAs/genética , Nácar/genética , Unionidae/genética , Exoesqueleto/anatomia & histologia , Animais , Cor , Hepatopâncreas/metabolismo , Sequenciamento de Nucleotídeos em Larga Escala , MicroRNAs/classificação , MicroRNAs/metabolismo , Anotação de Sequência Molecular , Nácar/metabolismo , Unionidae/anatomia & histologia , Unionidae/metabolismo , beta Caroteno/biossíntese
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