Defining the limits of physiological plasticity: how gene expression can assess and predict the consequences of ocean change

Abstract

Anthropogenic stressors, such as climate change, are driving fundamental shifts in the abiotic characteristics of marine ecosystems. As the environmental aspects of our world's oceans deviate from evolved norms, of major concern is whether extant marine species possess the capacity to cope with such rapid change. In what many scientists consider the post-genomic era, tools that exploit the availability of DNA sequence information are being increasingly recognized as relevant to questions surrounding ocean change and marine conservation. In this review, we highlight the application of high-throughput gene-expression profiling, primarily transcriptomics, to the field of marine conservation physiology. Through the use of case studies, we illustrate how gene expression can be used to standardize metrics of sub-lethal stress, track organism condition in natural environments and bypass phylogenetic barriers that hinder the application of other physiological techniques to conservation. When coupled with fine-scale monitoring of environmental variables, gene-expression profiling provides a powerful approach to conservation capable of informing diverse issues related to ocean change, from coral bleaching to the spread of invasive species. Integrating novel approaches capable of improving existing conservation strategies, including gene-expression profiling, will be critical to ensuring the ecological and economic health of the global ocean.

Characterization and Identification of Differentially Expressed Genes Involved in Thermal Adaptation of the Hong Kong Oyster Crassostrea hongkongensis by Digital Gene Expression Profiling

“…Cytoskeleton proteins have dynamic structures, which help maintain cell shape, and aid in cellular division, cell movement and support. Changes in the expression of cytoskeletal gene transcripts in response to abiotic stress have been reported in many marine organisms (Lockwood and Somero, 2011;Evans and Hofmann, 2012). In the present study, exposure to thermal stress reduced the expression of genes involved in the formation of major cytoskeletal structures, such as tubulin (0.47-fold compared to the control group), and myosin (0.31-fold compared to the control group).…”

Exploring local adaptation and the ocean acidification seascape – studies in the California Current Large Marine Ecosystem

“…This information may indicate areas that might be refuges from acidification in the future, and could reveal regions that are adaptation "hot spots"; i.e., places where selection for undersaturation-tolerant genotypes has been underway for long periods of time (Jacobs et al, 2004). Finally, discovery of tolerant populations within the environmental mosaic of the CCLME can provide an opportunity to identify mechanisms that underlie tolerance (Evans et al, 2013a;Evans and Hofmann, 2012). We also hope to address whether some species possess sufficient physiological and genetic variation to adapt to future change.…”

The Role of Transcriptomics: Physiological Equivalence Based on Gene Expression Profiles

“…Many studies have used DNA microarrays to infer how organisms respond to different environments (Gracey and Cossins, 2003;Cossins et al, 2006;Gracey, 2007;Evans and Hofmann, 2012), such as temperature Yang et al, 2010;Long et al, 2012;Aguado-Urda et al, 2013;Logan and Buckley, 2015), osmolality (Posas et al, 2000;Evans and Somero, 2008;Melamed et al, 2008;Halbeisen andGerber, 2009), oxygen (Ton et al, 2003;Garnczarska, 2006;Swiderek et al, 2008;Otsuka et al, 2010;Gracey et al, 2011;Shinde et al, 2015) and pH (Leaphart et al, 2006;Serrano et al, 2006;Worden et al, 2009;Evans et al, 2013). Detection of genes with expression changes in response to environmental change helps to predict the fragility, resistance, and adaptability of an organism, tissue, or cell in the environment.…”