Regulation of vitellogenesis in Nereis virens (Annelida: Polychaeta): effect of estradiol-17beta on eleocytes.

Abstract In the marine polychaete Nereis virens , the yolk protein precursor vitellogenin (Vg) is synthesized in specialized coelomic cells (eleocytes) during oogenesis. This process was visualized by immunohistochemistry using antibodies raised against the yolk protein. Transversal sections from male and female worms confirmed that eleocytes from females but not from males produce Vg. In order to investigate the hormonal regulation of Vg synthesis, eleocytes were incubated in vitro with estradiol-17β (E 2 ) at a concentration of 1 μg/l for up to three days. A strong increase in Vg secretion was detected by ELISA in culture media of treated eleocytes from vitellogenic females. In contrast, …