Neuropeptides regulate shell growth in the Mediterranean mussel (Mytilus galloprovincialis).

In bivalves, which are molluscs enclosed in a biomineralized shell, a diversity of neuropeptide precursors has been described but their involvement in shell growth has been largely neglected. Here, using a symmetric marine bivalve, the Mediterranean mussel (Mytilus galloprovincialis), we uncover a role for the neuroendocrine system and neuropeptides in shell production. We demonstrate that the mantle is rich in neuropeptide precursors and that a complex network of neuropeptide-secreting fibres innervates the mantle edge a region highly involved in shell growth.

Evolution of chitin-synthase in molluscs and their response to ocean acidification.

Chitin-synthase (CHS) is found in most eukaryotes and has a complex evolutionary history. Research into CHS has mainly been in the context of biomineralization of mollusc shells an area of high interest due to the consequences of ocean acidification. Exploration of CHS at the genomic level in molluscs, the evolution of isoforms, their tissue distribution, and response to environmental challenges are largely unknown.

Differential tissue immune stimulation through immersion in bacterial and viral agonists in the Antarctic Notothenia rossii.

The genome evolution of Antarctic notothenioids has been modulated by their extreme environment over millennia and more recently by human-caused constraints such as overfishing and climate change. Here we investigated the characteristics of the immune system in Notothenia rossii and how it responds to 8 h immersion in viral (Poly I:C, polyinosinic: polycytidylic acid) and bacterial (LPS, lipopolysaccharide) proxies. Blood plasma antiprotease activity and haematocrit were reduced in Poly I:C-treated fish only, while plasma protein, lysozyme activity and cortisol were unchanged with both treatments.

Revisiting the evolution of Family B1 GPCRs and ligands: Insights from mollusca.

Family B1 G protein-coupled receptors (GPCRs) are one of the most well studied neuropeptide receptor families since they play a central role in many biological processes including endocrine, gastrointestinal, cardiovascular and reproduction in animals. The genes for these receptors emerged from a common ancestral gene in bilaterian genomes and evolved via gene/genome duplications and deletions in vertebrate and invertebrate genomes. Their existence and function have mostly been characterized in vertebrates and few studies exist in invertebrate species.

The physiological effect of polystyrene nanoplastic particles on fish and human fibroblasts.

Numerous studies have identified the detrimental effects for the biosphere of large plastic debris, the effect of microplastics (MPs) and nanoplastics (NPs) is less clear. The skin is the first point of contact with NPs, and skin fibroblasts have a vital role in maintaining skin structure and function. Here, a comparative approach is taken using three fibroblast cell lines from the zebrafish (SJD.

Core genes of biomineralization and cis-regulatory long non-coding RNA regulate shell growth in bivalves.

Introduction: Bivalve molluscs are abundant in marine and freshwater systems and contribute essential ecosystem services. They are characterized by an exuberant diversity of biomineralized shells and typically have two symmetric valves (a.k.

Domain-Dependent Evolution Explains Functional Homology of Protostome and Deuterostome Complement C3-Like Proteins.

Complement proteins emerged early in evolution but outside the vertebrate clade they are poorly characterized. An evolutionary model of C3 family members revealed that in contrast to vertebrates the evolutionary trajectory of genes in cnidarian, protostomes and invertebrate deuterostomes was highly divergent due to independent lineage and species-specific duplications. The deduced and vertebrate C3, C4 and C5 proteins had low sequence conservation, but extraordinarily high structural conservation and 2-chain and 3-chain protein isoforms repeatedly emerged.

The temptin gene of the clade Lophotrochozoa is involved in formation of the prismatic layer during biomineralization in molluscs.

The biomineralization mechanism of mollusc shell has been studied for a long time, but there is a lack of understanding about the relationship between the shell formation in vitro and the signaling system in vivo. In this study, we cloned a novel shell matrix protein gene (hc-temptin), which only be characterized as a water-borne protein pheromone of molluscs in previous studies, from the freshwater mussel Hyriopsis cumingii. By bioinformatics analysis we found that temptin was a gene unique to the clade Lophotrochozoa, and it exists in all mollusc taxa except Cephalopoda.

RNAi-mediated knock-down of the dopamine beta-hydroxylase gene changes growth of razor clams.

Dopamine beta-hydroxylase (DβH) plays an essential role in the synthesis of catecholamines (CA) in neuroendocrine networks. In the razor clam, Sinonovacula constricta a novel gene for DβH (ScDβH-α) was identified that belongs to the copper type II ascorbate-dependent monooxygenase family. Expression analysis revealed ScDβH-α gene transcripts were abundant in the liver and expressed throughout development.

The calcitonin-like system is an ancient regulatory system of biomineralization.

Biomineralization is the process by which living organisms acquired the capacity to accumulate minerals in tissues. Shells are the biomineralized exoskeleton of marine molluscs produced by the mantle but factors that regulate mantle shell building are still enigmatic. This study sought to identify candidate regulatory factors of molluscan shell mineralization and targeted family B G-protein coupled receptors (GPCRs) and ligands that include calcium regulatory factors in vertebrates, such as calcitonin (CALC).

Dopamine beta-hydroxylase and its role in regulating the growth and larval metamorphosis in Sinonovacula constricta.

Dopamine beta-hydroxylase (DβH) plays a key role in the synthesis of catecholamines (CAs) in the neuroendocrine regulatory network. The DβH gene was identified from the razor clam Sinonovacula constricta and referred to as ScDβH. The ScDβH gene is a copper type II ascorbate-dependent monooxygenase with a DOMON domain and two Cu2_monooxygen domains.

A four-CRD C-type lectin from razor clam Sinonovacula constricta mediates agglutination and phagocytosis.

C-type lectins are a superfamily of Ca-dependent carbohydrate-binding proteins that play crucial roles in invertebrate immunity. In this study, a novel C-type lectin gene (ScCTL-1) was identified in razor clam Sinonovacula constricta. The ScCTL-1 gene, consisting of four C-type carbohydrate recognition domains (CRDs) with an N-terminal signal peptide and a C-terminal transmembrane region.

Complement factor B/C2 in molluscs regulates agglutination and illuminates evolution of the Bf/C2 family.

Complement factor B/C2 family (Bf/C2F) proteins are core complement system components in vertebrates that are absent in invertebrates and have been lost by numerous species, raising evolutionary questions. At least 3 duplication events have occurred from Cnidaria (ancestor) to mammals. Type II Bf/C2 genes appeared during separation of Proterostomia and Deuterostomes.

Tolerance, Growth, and Physiological Responses of the Juvenile Razor Clam () to Environmental Ca and Mg Concentrations.

To facilitate transplanting razor clam () populations to inland saline-alkaline waters (ISWs), we evaluated the tolerance of juvenile (JSC) to Ca and Mg concentrations, and determined the effects of these ions on JSC growth and physiological parameters. After 30 days stress, the tolerable ranges of JSC to Ca and Mg were determined to be 0.19 mmol⋅L-19.

Survival, growth and physiology of marine bivalve (Sinonovacula constricta) in long-term low-salt culture.

In this study, we investigated the possibility of rearing and breeding the razor clam (Sinonovacula constricta) in inland low salinity water or freshwater. Long-term low salinity (LS) rearing was performed for 3 months to determine the effects of LS on the survival rate, growth rate, and the activities of critical enzymes in juvenile S. constricta (JSC).

Characterization of the ScghC1q-1 gene in Sinonovacula constricta and its role in innate immune responses.

C1q is an important immune gene that can mediate a variety of immune regulatory functions, and is involved in complement pathway activation. In the present study, a ghC1q gene from the razor clam Sinonovacula constricta was identified and named ScghC1q-1. The complete ScghC1q-1 gene is 692 bp in length, with an open reading frame (ORF) of 489 bp encoding a protein of 162 amino acids.

Identification of a novel C1q complement component in razor clam Sinonovacula constricta and its role in antibacterial activity.

The serum complement component C1q mediates a variety of immune regulatory functions. Herein, we identified a globular head C1q (ghC1q) gene in razor clam Sinonovacula constricta. The complete Sc-ghC1q gene was 872 bp long included an 81 bp 5'-untranslated region (UTR), a 95 bp 3'-UTR with a poly(A) tail, and an open reading frame (ORF) of 696 bp.

Identification and characterisation of a novel small galectin in razor clam (Sinonovacula constricta) with multiple innate immune functions.

Galectins are lectins possessing an evolutionarily conserved carbohydrate recognition domain (CRD) with affinity for β-galactoside. The key role played by innate immunity in invertebrates has recently become apparent. Herein, a full-length galectin (ScGal) was identified in razor clam (Sinonovacula constricta).

Effects of Alkalinity and pH on Survival, Growth, and Enzyme Activities in Juveniles of the Razor Clam, .

In order to clarify the possibility of rearing razor clams () in inland saline water (ISW) and to facilitate their breeding under these stressful conditions, we performed semi-static acute and chronic toxicity tests to determine the effects of carbonate alkalinity (CA) and pH on the survival and growth rate, and critical metabolic enzyme activity in juvenile of (JSC). (1) Acute toxicity test. As the water increased from 1.

Identification of a novel galectin in Sinonovacula constricta and its role in recognition of Gram-negative bacteria.

Galectins are soluble lectins that perform a pattern recognition function in invertebrate immunity and specifically recognise β-galactoside residues via conserved carbohydrate recognition domains. However, their function in bivalve molluscs has received little attention. Herein, a galectin (ScGal2) in razor clam (Sinonovacula constricta) consisting of a 507 bp open reading frame encoding a protein of 168 amino acids was identified and characterised.

Hemolytic reactions in the hemolymph of bivalve Sinonovacula constricta show complement-like activity.

The complement-like hemolysis method was used to determine the total complement-like activity of the plasma of Sinonovacula constricta. In this study, the effects of both physical and chemical conditions on complement hemolysis of S. constricta were measured.

Expression of a novel complement C3 gene in the razor clam Sinonovacula constricta and its role in innate immune response and hemolysis.

Complement component 3 (C3) is a core component of the complement system, and directly participates in immune regulation and immune defense. Isoforms of C3 have been reported in several species of vertebrate, but invertebrates, and more specifically clams, have been less well studied. An isoform of C3, named ScC3-2, was identified in Sinonovacula constricta (Chinese razor clam).

Complement C3 gene: Expression characterization and innate immune response in razor clam Sinonovacula constricta.

Complement component 3 (C3) is central to the complement system, playing an important role in immune defense, immune regulation and immune pathology. Several C3 genes have been characterized in invertebrates but very few in shellfish. The C3 gene was identified from the razor clam Sinonovacula constricta, referred to here as Sc-C3.

Developmental Transcriptome Analysis and Identification of Genes Involved in Larval Metamorphosis of the Razor Clam, Sinonovacula constricta.

The razor clam Sinonovacula constricta is an important commercial species. The deficiency of developmental transcriptomic data is becoming the bottleneck of further researches on the mechanisms underlying settlement and metamorphosis in early development. In this study, de novo transcriptome sequencing was performed for S.