Isolation and Pathogenic Characterization of Vibrio bivalvicida Associated With a Massive Larval Mortality Event in a Commercial Hatchery of Scallop Argopecten purpuratus in Chile

AbstractMethoprene-tolerant (Met) is a putative JH intracellular receptor that transduces JH signal by activation of the inducible Krüppel homolog 1 (Kr-h1). We analyzed the gene sequences of Met and Kr-h1 and their patterns of expression in Grapholita molesta (Busck) immature and adult stages in order to better understand the roles of these primary JH responders in regulating the metamorphosis and reproduction of this global pest of fruit crops. The deduced amino acid sequences of both GmMet and GmKr-h1 were highly homologous to those of other Lepidoptera, especially the cotton bollworm, Helicoverpa armigera (Hubner) (Lepidoptera: Noctuidae). Peak expression of GmMet occurred during the last 3 to 5 d of the final instar, followed by that of GmKr-h1, in the last 3 d of final instar. Similar patterns of GmMet and GmKr-h1 expression were detected across various tissue types in the fifth-instar larvae, with the highest expression observed in the head, followed by the epidermis, and the fat body. When expression of GmMet and GmKr-h1 was knocked down via dsRNA injection in the fifth instar, the results were increased larval mortality, abnormal pupation, delayed pupal duration, reduced adult emergence, extended preoviposition period, and reduced fecundity. We infer that both GmMet and GmKr-h1 participated in regulation of metamorphosis and reproduction in G. molesta, the former acting upstream of the latter, and could present biorational targets for novel pest control compounds.

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Molecular characterization of two ferritins of the scallop Argopecten purpuratus and gene expressions in association with early development, immune response and growth rate

Comparative Biochemistry and Physiology Part B Biochemistry and Molecular Biology ◽

10.1016/j.cbpb.2016.03.007 ◽

2016 ◽

Vol 198 ◽

pp. 46-56 ◽

Cited By ~ 13

Author(s):

Teodoro Coba de la Peña ◽

Claudia B. Cárcamo ◽

María I. Díaz ◽

Katherina B. Brokordt ◽

Federico M. Winkler

Keyword(s):

Immune Response ◽

Growth Rate ◽

Molecular Characterization ◽

Early Development ◽

Gene Expressions ◽

Argopecten Purpuratus

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Coupled microbiome analyses highlights relative functional roles of bacteria in a bivalve hatchery

Environmental Microbiome ◽

10.1186/s40793-021-00376-z ◽

2021 ◽

Vol 16 (1) ◽

Author(s):

Emma Timmins-Schiffman ◽

Samuel J. White ◽

Rhonda Elliott Thompson ◽

Brent Vadopalas ◽

Benoit Eudeline ◽

...

Keyword(s):

Larval Mortality ◽

Trophic Relationships ◽

Functional Roles ◽

Complementary Methods ◽

Full Characterization ◽

Host Health ◽

Pathogenic Microbes ◽

Species Specific ◽

Bivalve Hatchery

Abstract Background Microbial communities are ubiquitous throughout ecosystems and are commensal with hosts across taxonomic boundaries. Environmental and species-specific microbiomes are instrumental in maintaining ecosystem and host health, respectively. The introduction of pathogenic microbes that shift microbiome community structure can lead to illness and death. Understanding the dynamics of microbiomes across a diversity of environments and hosts will help us to better understand which taxa forecast survival and which forecast mortality events. Results We characterized the bacterial community microbiome in the water of a commercial shellfish hatchery in Washington state, USA, where the hatchery has been plagued by recurring and unexplained larval mortality events. By applying the complementary methods of metagenomics and metaproteomics we were able to more fully characterize the bacterial taxa in the hatchery at high (pH 8.2) and low (pH 7.1) pH that were metabolically active versus present but not contributing metabolically. There were shifts in the taxonomy and functional profile of the microbiome between pH and over time. Based on detected metagenomic reads and metaproteomic peptide spectral matches, some taxa were more metabolically active than expected based on presence alone (Deltaproteobacteria, Alphaproteobacteria) and some were less metabolically active than expected (e.g., Betaproteobacteria, Cytophagia). There was little correlation between potential and realized metabolic function based on Gene Ontology analysis of detected genes and peptides. Conclusion The complementary methods of metagenomics and metaproteomics contribute to a more full characterization of bacterial taxa that are potentially active versus truly metabolically active and thus impact water quality and inter-trophic relationships.

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