Meeting Abstract
Polybrominated diphenyl ethers (PBDEs) are environmentally ubiquitous flame retardants that have been linked with altered endocrine function in a variety of organisms. A recent study identified BDE-28, one of the most prevalent PBDE congeners in aquatic environments, as a potent inhibitor of crustacean molting, but the mechanism of its action is still unclear. This study will examine the disruptive effects of BDE-28 on epidermal ecdysteroid signaling in vitro to illuminate a potential mechanism for molt disruption by this PBDE congener. Expression of the N-acetyl-β-glucosaminidase (NAG) gene in the epidermis will be used as the biomarker for ecdysteroid signaling. Using the recently developed epidermis-with-exoskeleton (EWE) tissue culture method, we will expose Callinectes sapidus epidermal tissues to varying levels of BDE-28 alone and in combination with the molting hormone 20-HE. The effects of BDE-28 and the inducibility of NAG will be measured by quantifying NAG gene expression in exposed tissues using RT-PCR. Initial results indicate possible suppression of epidermal ecdysteroid signaling due to a trend of decreasing NAG gene expression between exposures to 1 µM 20-HE alone and the binary treatment of 1 µM 20-HE and 1 µM BDE-28. Findings of this study will ultimately contribute to an improved understanding of the mechanisms of molt-disruption by this environmentally important PBDE congener.
