PNNL

Abstract

In this study, we describe the sequence for the fathead minnow (Pimephales promelas) vitellogenin 3 gene (vg3), and compare the response of vg1 and vg3 following exposure to steroidal estrogens and androgens. The fathead minnow vg3 sequence is only the second nucleotide sequence described in teleosts, following the original description of this isoform in zebrafish (Danio rerio). Following a brief exposure (24 hours) to 2, 5, and 10 ng/L 17 alpha-ethynylestradiol (EE2), both vg1and vg3 are upregulated in male liver. However, levels of vg3 induction are 4 orders of magnitude lower than induction of vg1. Suppression of vg in female liver following androgenic exposure with 50 or 500 ng/L 17 beta-trenbolone occurs at similar significance levels for both vg1 and vg3 isoforms. The results of this study confirm the use of vg1 as an indicator of estrogenic exposure in male fish, and present the potential for vg1 and /or vg3 for use as indicators of androgenic exposure.