title: Epipodial Tentacle Gene Expression and Predetermined Resilience to Summer Mortality in the Commercially Important Greenlip Abalone, Haliotis laevigata.
abstract: "Summer mortality" is a phenomenon that occurs during warm water temperature spikes that results in the mass mortality of many ecologically and economically important mollusks such as abalone. This study aimed to determine whether the baseline gene expression of abalone before a laboratory-induced summer mortality event was associated with resilience to summer mortality. Tentacle transcriptomes of 35 greenlip abalone (Haliotis laevigata) were sequenced prior to the animals being exposed to an increase in water temperature-simulating conditions which have previously resulted in summer mortality. Abalone derived from three source locations with different environmental conditions were categorized as susceptible or resistant to summer mortality depending on whether they died or survived after the water temperature was increased. We detected two genes showing significantly higher expression in resilient abalone relative to susceptible abalone prior to the laboratory-induced summer mortality event. One of these genes was annotated through the NCBI non-redundant protein database using BLASTX to an anemone (Exaiptasia pallida) Transposon Ty3-G Gag Pol polyprotein. Distinct gene expression signatures were also found between resilient and susceptible abalone depending on the population origin, which may suggest divergence in local adaptation mechanisms for resilience. Many of these genes have been suggested to be involved in antioxidant and immune-related functions. The identification of these genes and their functional roles have enhanced our understanding of processes that may contribute to summer mortality in abalone. Our study supports the hypothesis that prestress gene expression signatures are indicative of the likelihood of summer mortality.
authors.affiliation: Department of Ecology, Environment and Evolution, School of Life Sciences, La Trobe University, Kingsbury Drive, Melbourne, VIC, 3086, Australia. bpshiel@students.latrobe.edu.au.
authors.forename: Brett P
authors.initials: BP
authors.lastname: Shiel
authors.affiliation: Department of Ecology, Environment and Evolution, School of Life Sciences, La Trobe University, Kingsbury Drive, Melbourne, VIC, 3086, Australia.|Life Sciences Computation Centre, VLSCI, Parkville, VIC, Australia.|Department of Molecular and Cell Biology, James Cook University, Townsville, Australia.
authors.forename: Nathan E
authors.initials: NE
authors.lastname: Hall
authors.affiliation: Life Sciences Computation Centre, VLSCI, Parkville, VIC, Australia.|Department of Molecular and Cell Biology, James Cook University, Townsville, Australia.|Department of Biochemistry, La Trobe Institute for Molecular Science, La Trobe University, Kingsbury Drive, Melbourne, VIC, 3086, Australia.
authors.forename: Ira R
authors.initials: IR
authors.lastname: Cooke
authors.affiliation: Nofima, P.O. Box 210, 1431, Ås, Norway.|Sustainable Aquaculture Laboratory-Temperate and Tropical (SALTT), School of BioSciences, The University of Melbourne, Parkville, VIC, 3010, Australia.
authors.forename: Nicholas A
authors.initials: NA
authors.lastname: Robinson
authors.affiliation: Department of Ecology, Environment and Evolution, School of Life Sciences, La Trobe University, Kingsbury Drive, Melbourne, VIC, 3086, Australia.|Centre for Sustainable Tropical Fisheries and Aquaculture, College of Science and Engineering, James Cook University, Townsville, QLD, 4811, Australia.
authors.forename: Jan M
authors.initials: JM
authors.lastname: Strugnell
mesh_terms: D000220:Adaptation, Biological; D000818:Animals; D017756:Aquaculture; D049851:Gastropoda / Q000235:genetics* / Q000502:physiology; D015870:Gene Expression; D006358:Hot Temperature; D013021:South Australia
keywords: Abalone; Aquaculture; Differential gene expression; Heat stress; Mollusk; RNA-seq; Transcriptomics