Temporal expression of cumulus cell marker genes during in vitro maturation and oocyte developmental competence
Cumulus cells (CC) play important roles in oocyte development and cumulus expressed genes can be used as markers for oocyte quality. This study aimed to investigate temporal changes in the expression of cumulus marker genes during oocyte maturation as possible biomarkers of embryo developmental competence in ovine.
Gene expression was assessed in the CC of the BCB+ (developmentally competent) and BCB- (developmentally poor) oocytes at 0, 12, and 24 h of in vitro maturation (IVM). Further, the association between the temporal cumulus gene expression and in vitro oocyte and embryo development was assessed.
The maturation and blastocyst formation rates were found significantly greater for the BCB+ than the BCB- oocytes. At the 0 h of IVM, a significant upregulation in the expression of PTGS2, STAR, SDC2, LHR, FGF2, BCL2, IL7RA, HSPA1A, and IFNT was observed in the CC of the poor (BCB-) as compared to the competent (BCB+) oocytes. In contrast, it was observed that as maturation progressed, the cumulus expression of most of the favorable genes was reduced and was found significantly downregulated at the completion of IVM in the poor as compared to the competent oocytes.
The study revealed noticeable differences in the cumulus gene expression profile at different stages of IVM between ovine oocytes of differential developmental ability. The results indicated that the loss of cumulus gene expression along the maturation period in the poor oocytes was related to their intrinsic poor quality in the ovarian follicle.
KeywordsGene expression Cumulus cells Oocyte Embryo In vitro development Ovine
This work was supported by the ICAR-National Agricultural Science Fund (grant number NFBSFARA/BSA-4005/2013-14).
- 18.Johnson KM, Alvarez X, Kubisch HM. Localization of interferon-tau in bovine embryos and cumulus cells by confocal microscopy. Reprod Fertil Dev 2004;16:239.Google Scholar
- 19.Dhali A, Anchamparuthy VM, Butler SP, Pearson RE, Gwazdauskas FC. In vitro development of bovine embryos cultured with stem cell factor or insulin-like growth factor-I following IVF with semen of two bulls having different field fertility. Anim Reprod Sci. 2009;116:188–95.CrossRefPubMedGoogle Scholar
- 24.Almeida AP, Saraiva MV, Alves Filho JG, Silva GM, Gonçalves RF, Brito IR, et al. Gene expression and immunolocalization of fibroblast growth factor 2 in the ovary and its effect on the in vitro culture of caprine preantral ovarian follicles. Reprod Domest Anim. 2012;47:20–5.CrossRefPubMedGoogle Scholar
- 27.Catala MG, Izquierdo D, Uzbekova S, Morato R, Roura M, Romaguera R, et al. Brilliant cresyl blue stain selects largest oocytes with highest mitochondrial activity, maturation-promoting factor activity and embryo developmental competence in prepubertal sheep. Reproduction. 2011;142:517–27.CrossRefPubMedGoogle Scholar
- 32.Mohammadi-Sangcheshmeh A, Veshkini A, Hajarizadeh A, Jamshidi-Adegani F, Zhandi M, Abazari-Kia AH, et al. Association of glucose-6-phosphate dehydrogenase activity with oocyte cytoplasmic lipid content, developmental competence, and expression of candidate genes in a sheep model. J Assist Reprod Genet. 2014;31:1089–98.CrossRefPubMedPubMedCentralGoogle Scholar
- 34.Calder MD, Caveney AN, Westhusin ME, Watson AJ. Cyclooxygenase-2 and prostaglandin E(2)(PGE(2)) receptor messenger RNAs are affected by bovine oocyte maturation time and cumulus-oocyte complex quality, and PGE(2) induces moderate expansion of the bovine cumulus in vitro. Biol Reprod. 2001;65:135–40.CrossRefPubMedGoogle Scholar