The Fate of Ovarian Somatic Cells during Sex Change in the Protogynous Wrasse, Halichoeres trimaculatus

摘要

The three-spot wrasse (Halichoeres trimaculatus)changes sex from female to male. Oocytes disappearcompletely, and male germ cells and somatic cellscomprising testicular tissue arise anew during theprocess of sex change [1]. However, little is knownabout the fate of germ and somatic cells during sexchange. In our previous study, we analyzed cellularbehavior (apoptosis and cell proliferation) in the sexchanging gonads [2]. Unexpectedly, few apoptoticsomatic cells were found to be present during sexchange. Interestingly, in gonads at an early stage of sexchange, cell proliferation was detected in manygranulosa cells surrounding the degenerating oocytes, afew epithelial cells covering ovigerous lamella andsomatic cells associated with gonial germ cells. Theseresults suggest that ovarian somatic cells survive duringthe regression of ovarian tissue. In the present study, weinvestigated the fate of ovarian somatic cells during sexchange by tracking proliferating somatic cells.