Datasets / Zebrafish gene expression, histology, blood domoic acid level, and behavioral data (Effects of Chronic Domoic Acid Exposure on Gene Expression in the Vertebrate CNS.)


Zebrafish gene expression, histology, blood domoic acid level, and behavioral data (Effects of Chronic Domoic Acid Exposure on Gene Expression in the Vertebrate CNS.)

Published By National Oceanic and Atmospheric Administration, Department of Commerce

Issued about 9 years ago

US
beta

Summary

Type of release
a one-off release of a set of related datasets

Data Licence
Not Applicable

Content Licence
Creative Commons CCZero

Verification
automatically awarded

Description

The potential impacts of chronic algal toxin exposure have long been a concern. One HAB toxin, domoic acid (DA), is a potent neurotoxin that interacts with the vertebrate central nervous system (CNS). Although the clinical signs of acute DA toxicity have been well defined, virtually nothing is known about the impacts of chronic, low-level toxin exposure, primarily due to the difficulties associated with long-term exposure studies. We know that vertebrates such as fish, seabirds, marine mammals, and humans are exposed to DA on a regular basis at levels below those that cause outward signs of toxicity, yet we have no idea how these chronic sub-acute exposures may impact these organisms. In this study, we use global gene expression in whole brain and morphological aberrations in major organ systems as endpoints to examine the effects of chronic exposure. The overall goal of this project is to develop a general model for the characterization of gene expression effects in the vertebrate CNS and morphological damage in major organs associated with long-term, low-level toxin exposure.Objectives-The objectives of the proposed study are to 1) quantify gene expression changes in the vertebrate CNS and characterize differentially expressed genes based on function to identify potential pathways of chronic disease associated with long-term, low-level algal toxin exposure, 2) quantify actual blood toxin levels associated with changes in gene expression, and 3) perform histologic examinations of all major organ systems to characterize morphological impacts of chronic toxicity.Approach-Our approach will be to use microchip gene array technology to quantify differential gene expression in whole brain during a one-year DA exposure study using a vertebrate model system (zebrafish, Danio rerio). Through pilot studies, we have quantified appropriate sub-acute doses, developed effective repetitive dosing procedures, and developed a statistically rigorous experimental design. We have also perfected RNA isolation methods, microchip array procedures, qRT-PCR confirmation procedures, and bioinformatics processes for grouping and identifying genes. In addition to gene expression analyses, we will use standard histology procedures to visualize potential morphological aberrations caused by chronic DA exposure.Expected Results- We expect this research will yield several results that will directly aid assessments of HAB impacts on ecosystems. First, the proposed project will provide the first available data on the impacts of chronic, low-level algal toxin exposure using a realistic long-term exposure time scale. It is also likely that new pathways of DA toxicity will be identified since a single dose exposure pilot study has already revealed gene expression patterns unique to sub-acute exposure. The gene lists generated will be widely disseminated and publicly available for researchers to use as a starting point for species-specific studies on chronic HAB toxin exposure effects. Finally, the study will quantify actual blood toxin levels that are associated with the observed gene expression effects. These blood toxin levels can be used for characterizing the potential risk to other vertebrates exposed to DA in the field. Gene expression data, blood DA levels, brain histology, survival, mitochondrial function, behavior and dose response data.