Analysis of Endocrine Disruption in Southern California Coastal Fish Using an Aquatic Multispecies Microarray

Abstract

BackgroundEndocrine disruptors include plasticizers, pesticides, detergents, and pharmaceuticals. Turbot and other flatfish are used to characterize the presence of chemicals in the marine environment. Unfortunately, there are relatively few genes of turbot and other flatfish in GenBank, which limits the use of molecular tools such as microarrays and quantitative reverse-transcriptase polymerase chain reaction (qRT-PCR) to study disruption of endocrine responses in sentinel fish captured by regulatory agencies.ObjectivesWe fabricated a multigene cross-species microarray as a diagnostic tool to screen the effects of environmental chemicals in fish, for which there is minimal genomic information. The array included genes that are involved in the actions of adrenal and sex steroids, thyroid hormone, and xenobiotic responses. This microarray will provide a sensitive tool for screening for the presence of chemicals with adverse effects on endocrine responses in coastal fish species.MethodsWe used a custom multispecies microarray to study gene expression in wild hornyhead turbot (Pleuronichthys verticalis) collected from polluted and clean coastal waters and in laboratory male zebrafish (Danio rerio) after exposure to estradiol and 4-nonylphenol. We measured gene-specific expression in turbot liver by qRT-PCR and correlated it to microarray data.ResultsMicroarray and qRT-PCR analyses of livers from turbot collected from polluted areas revealed altered gene expression profiles compared with those from nonaffected areas.ConclusionsThe agreement between the array data and qRT-PCR analyses validates this multispecies microarray. The microarray measurement of gene expression in zebrafish, which are phylogenetically distant from turbot, indicates that this multispecies microarray will be useful for measuring endocrine responses in other fish.

Developmental and Extracellular Matrix-Remodeling Processes in Rosiglitazone-Exposed Neonatal rat Cardiomyocytes

“…Data are presented as a heat map of relative over- and under-expression in rosiglitazone treated with respect to control DMSO treated NRVMs (Figure 6). Q-PCR was carried out as described previously [36]. This revealed that these transcripts were progressively upregulated as the time course proceeded and validated the array data.…”

Life Histories, Salinity Zones, and Sublethal Contributions of Contaminants to Pelagic Fish Declines Illustrated with a Case Study of San Francisco Estuary, California, USA

“…For example, molecular biomarkers such as thyroid hormone levels or gene expression (Baker et al 2009;Brar et al 2010), when coupled with histological assays of body condition, can reveal the energetic consequences of suppressed thyroid function and tumor growth in wild-caught organisms. Field studies are important in determining how energetic responses to contaminants are mediated by diel temperature variability, seasonal hydrology, resource availability, and predator-prey relationships (Clark and Clements 2006;Buchwalter et al 2007).…”

Hepatic gene expression in flounder chronically exposed to multiply polluted estuarine sediment: Absence of classical exposure ‘biomarker’ signals and induction of inflammatory, innate immune and apoptotic pathways

“…Thus, when comparing a highly PAH-contaminated environment with a 'clean' reference site, flounder transcripts characteristic of acute PAH-response were changed (Williams et al, 2003). Similarly, when comparing hornyhead turbot (Pleuronichthys verticalis) from a site receiving an estrogenic effluent with a clean site, a signal characteristic of acute estrogen exposure was observed (Baker et al, 2009). However, in a larger study, involving several European estuaries of differing pollutant status, and using a more comprehensive microarray, a transcriptomic signal of pollutant effect was less clear (Falciani et al, 2008).…”