Meeting Abstract

P2.144  Thursday, Jan. 5  Histological structure and mRNA in situ hybridization in the ovary of the banana shrimp (Fenneropenaeus merguiensis de Man) PUENGYAM, Peerapong*; UTARABHAND, Prapaporn; TSUKIMURA, Brian; Prince of Songkla University, Thailand; Prince of Songkla University, Thailand; California State University, Fresno

Vitellogenin (Vg) is the precursor to yolk protein that supplies nutrients for embryonic development. Thrombospondin (TSP) is a major component of the cortical rod proteins in the ovary of penaeid shrimps. In this study, the histochemistry and in situ hybridization analysis were used to examine the structure and localization of Vg and TSP mRNA in the ovarian tissue of the banana shrimp, Fenneropenaeus merguiensis. Mature ovaries show high accumulation of yolk granules and the rod-like bodies of cortical protein at the periphery of the yolky oocytes. The crypts became elongated and extended to the nucleus. The localization of mRNA transcripts in the ovary was visualized with RNA probes by in situ hybridization. The Vg mRNA was only detected in the follicle cells of vitellogenic ovaries, whereas the TSP mRNA was found in primary oocytes including previtellogenic and early vitellogenic oocytes, (and not in oogonia, mature oocytes, follicle cells and connective tissues). In the banana shrimp, the Vg mRNA may be transcribed and subsequently translated into the Vg precursor in follicle cells, and then taken up into oocytes for yolk accumulation. The TSP was expressed in the early stages of ovarian development and may be important for cortical rod formation in the oocytes. These results suggest that the expression of Vg and TSP gene may play an important role in ovarian maturation but their expression regulation mechanisms are different. Further study of mRNA expression of Vg and TSP is necessary to understand ovarian maturation in penaeid shrimps.