Abstract
The maturation of an oocyte into an egg is a key step in preparation for fertilization. In Xenopus, oocyte maturation is independent of transcription, being regulated at the level of translation and post-translational modifications of proteins. To identify factors involved in the maturation process we used two-dimensional differential gel electrophoresis to compare the proteome of oocytes and eggs. Protein abundance changes were observed in multiple cellular pathways during oocyte maturation. Most prominent was a general reduction in abundance of enzymes in the glycolytic pathway. Injection into oocytes of the glycolytic intermediates glyceraldehyde-3-phosphate, phosphoenolpyruvate and glucose-6-phosphate prevented oocyte maturation. Instead, these metabolites stimulated ROS production and subsequent apoptosis of the oocyte. In contrast, all other metabolites tested had no effect on oocyte maturation and did not induce apoptosis. These data suggest that a subset of glycolytic metabolites have the capacity to regulate oocyte viability.
Highlights
The maturation of an oocyte into a fertilizable egg is the final stage of oogenesis that must be carefully controlled to coincide with the reproductive cycle of the animal
As Xenopus oocyte maturation is regulated post transcriptionally through changes to the proteome, we sought to identify differences in the proteome that occur during the maturation of a stage VI oocyte using two-dimensional differential gel electrophoresis (2D-DIGE)
Lysates were prepared from surgically isolated stage VI oocytes and stage VI oocytes from the same animal that had been matured by incubation in progesterone until white spot formation (WSF)
Summary
The maturation of an oocyte into a fertilizable egg is the final stage of oogenesis that must be carefully controlled to coincide with the reproductive cycle of the animal. During maturation the Xenopus oocyte goes through many changes [1,2] including changes in metabolism [3]. Disruption of metabolic pathways can have significant consequences on the viability of matured oocytes, eggs and early development [4,5,6]. The final stage of oocyte maturation is stimulated by the hormone progesterone, or a closely related metabolite [9,10]. Xenopus oocyte maturation is not regulated by transcription. Oocyte maturation is regulated at the level of translation and through the post-translational modification of proteins [1,2]. The resulting changes to the proteome, both abundance and protein modifications are responsible for the signaling pathways that mature the oocyte
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
