Korean J Reprod Med.  2007 Jun;34(2):95-106.

Species-specific Expression of Rpia Transcript in Cumulus-oocyte-complex

• Kim YS
• Yoon SJ
• Kim EY
• Lee KA

Abstract

OBJECTIVE
We previously identified differentially expressed genes (DEGs) between germinal vesicle (GV) and metaphase II (MII) mouse oocyte.(1) The present study was accomplished as a preliminary study to elucidate the role of ribose 5-phosphate isomerase A (Rpia), the essential enzyme of the pentose phosphate pathway (PPP), in oocyte maturation. We observed expression of Rpia in the mouse and porcine oocytes.
METHODS
Expression pattern of the 11 MII-selective DEGs in various tissues was evaluated using RT-PCR and selected 4 genes highly expressed in the ovary. According to the oocyte-selective expression profile, we selected Rpia as a target for this study. We identified the porcine Rpia sequence using EST clustering technique, since it is not yet registered in public databases. RESULT: The extended porcine Rpia nucleotide sequence was submitted and registered to GenBank (accession number EF213106). We prepared primers for porcine Rpia according to this sequence. In contrast to the oocyte-specific expression in the mouse, Rpia was expressed in porcine cumulus and granulosa cells as well as in oocytes.
CONCLUSION
This is the first report on the characterization of the Rpia gene in the mouse and porcine ovarian cells. Results of the present study suggest that the mouse and porcine COCs employ different mechanism of glucose metabolism. Therefore, the different metabolic pathways during in vitro oocyte maturation (IVM) in different species may lead different maturation rates. It is required to study further regarding the role of Rpia in glucose metabolism of oocytes and follicular cell fore exploring the regulatory mechanism of oocyte maturation as well as for finding the finest culture conditions for in vitro maturation.

Keyword

EST clustering; in vitro maturation; Pentose phosphate pathway (PPP); Ribose 5-phosphate isomerase A(Rpia)

MeSH Terms

Animals
Base Sequence
Databases, Nucleic Acid
Female
Glucose
Granulosa Cells
In Vitro Oocyte Maturation Techniques
Metabolic Networks and Pathways
Metabolism
Metaphase
Mice
Oocytes
Ovary
Pentose Phosphate Pathway
Ribose
Glucose
Ribose