Analysis of Gene Expression in an Inbred Line of Soft-Shell Clams (Mya arenaria) Displaying Growth Heterosis: Regulation of Structural Genes and the NOD2 Pathway.
Mya arenariais a bivalve mollusk of commercial and economic importance, currently impacted by ocean warming, acidification, and invasive species. In order to inform studies on the growth ofM. arenaria, we selected and inbred a population of soft-shell clams for a fast-growth phenotype. This population displayed significantly faster growth (p< 0.0001), as measured by 35.4% greater shell size. To assess the biological basis of this growth heterosis, we characterized the complete transcriptomes of six individuals and identified differentially expressed genes by RNAseq. Pathways differentially expressed included structural gene pathways. Also differentially expressed was the nucleotide-binding oligomerization domain 2 (NOD2) receptor pathway that contributes to determination of growth, immunity, apoptosis, and proliferation. NOD2 pathway members that were upregulated included a subset of isoforms ofRIPK2(mean 3.3-fold increase in expression),ERK/MAPK14(3.8-fold),JNK/MAPK8(4.1-fold), andNFκB(4.08-fold). These transcriptomes will be useful resources for both the aquaculture community and researchers with an interest in mollusks and growth heterosis.
Division of Environmental and Biological Sciences, University of Maine at Machias, Machias, ME 04654, USA; The Jackson Laboratory, Bar Harbor, ME 04609, USA.
John J
0000-0001-7678-3062
JJ
Wilson
Division of Environmental and Biological Sciences, University of Maine at Machias, Machias, ME 04654, USA; Mount Desert Island Biological Laboratory, Salisbury Cove, ME 04672, USA.
Janelle
0000-0002-0561-2773
J
Grendler
Division of Environmental and Biological Sciences, University of Maine at Machias, Machias, ME 04654, USA.
Azaline
A
Dunlap-Smith
Division of Environmental and Biological Sciences, University of Maine at Machias, Machias, ME 04654, USA.
Brian F
0000-0001-9646-0180
BF
Beal
Division of Environmental and Biological Sciences, University of Maine at Machias, Machias, ME 04654, USA.
Shallee T
0000-0002-3557-4122
ST
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