Expression profiling of estrogenic compounds using a sheepshead minnow cDNA macroarray.

A variety of anthropogenic compounds are capable of binding to the estrogen receptor (ER) of vertebrate species. Binding of these chemicals to the ER can interfere with homeostasis by altering normal gene expression patterns. The purpose of this study was to characterize the expression of 30 genes using a sheepshead minnow (Cyprinodon variegatus) cDNA macroarray. Many of the genes on the array were previously identified by differential display reverse transcriptase-polymerase chain reaction to be upregulated or downregulated in sheepshead minnows treated through aqueous exposure to known or suspected estrogenic chemicals. The results of this study show that 17 beta-estradiol (E2), 17 alpha-ethinyl estradiol (EE2), diethylstilbestrol (DES), and methoxychlor (MXC) have similar genetic signatures for the 30 genes examined. The genetic signature of fish treated with p-nonylphenol was identical in pattern to that in fish treated with E2, EE2, DES, and MXC except for the additional upregulation of a cDNA clone that shares similarity to ubiquitin-conjugating enzyme 9. Endosulfan produced results that resembled the gene expression patterns of untreated control fish with exception of the upregulation of estrogen receptor alpha and the downregulation of a cDNA clone that shares similarity to 3-hydroxy-3-methylglutaryl-coenzyme A reductase. We show that our estrogen-responsive cDNA macroarray can detect dose-dependent changes in gene expression patterns in fish treated with EE2.

Array technology as a tool to monitor exposure of fish to xenoestrogens.

A variety of anthropogenic chemicals are capable of binding to the estrogen receptor of vertebrate species. Binding of these compounds can interfere with homeostasis by disrupting normal gene expression patterns. The purpose of this study was to investigate the feasibility of applying array technology as a monitoring tool for detecting the presence and distribution of estrogenic compounds in coastal habitats using sheepshead minnows as our model. cDNA clones that were isolated from differential display, including vitellogenin alpha and beta, vitelline envelope protein (ZP2), and transferrin, among others, were spotted on the macroarray. The results of these experiments demonstrate a characteristic expression pattern of estrogen responsive genes in sheepshead minnows exposed to 17 beta-estradiol (E2).