Type

Journal Article

Authors

Maurice P Boland
Julio de la Fuente
Belen Pintado
Dimitrios Rizos
Alfonso Gutierrez-Adan
Patrick Lonergan

Subjects

Biochemistry

Topics
growth differentiation factor 9 metabolism intercellular signaling peptides and proteins physiology glucose follicular phase oxidative stress animals cytology gene expression regulation developmental cyclins female polyadenylation cattle genetics gene expression profiling luteinizing hormone oocytes rna messenger monosaccharide transport proteins cells cultured embryonic and fetal development

Relative messenger RNA abundance in bovine oocytes collected in vitro or in vivo before and 20 hr after the preovulatory luteinizing hormone surge. (2003)

Abstract In the cyclic cow, final maturation of the ovulatory follicle is initiated by the preovulatory luteinizing hormone (LH) surge. During the subsequent 24 hr period, the oocyte nucleus undergoes meiotic progression to metaphase II and several changes in cytoplasmic organization take place. We have previously shown that oocytes recovered at the time of the LH peak and matured in vitro are less competent to reach the blastocyst stage than their counterparts recovered 20 hr later following in vivo maturation, despite both groups undergoing IVF and culture in parallel. The objective of this study was to compare, using real-time quantitative RT-PCR, the relative abundance of various developmentally important gene transcripts in these oocytes. The groups used were mature bovine oocytes originating from: (1) 2-6 mm follicles from slaughterhouse ovaries; (2) preovulatory follicles punctured by ovum pick-up just before the LH surge (i.e., immature) and matured in vitro; or (3) preovulatory follicles punctured 20 hr later, just prior to ovulation (i.e., in vivo matured). In addition, immature oocytes from 2-6 mm follicles were examined. We examined the relative mRNA expression of five enzymes involved in protection against free oxygen radicals (mitochondrial Mn-superoxide dismutase, MnSOD, cytosolic Cu/Zn superoxide dismutase, Cu/ZnSOD, gamma-glutamyl-cysteine transferase, GCS, glutathione peroxidase, GPX, sarcosine oxidase, SOX), a transcript involved in follicular development (growth differentiation factor-9, GDF-9), transcripts involved in glucose metabolism (glucose-6-phosphate dehydrogenase, G6PDH, glucose transporter type-1 and -8, Glut-1, Glut-8) and genes involved in cell cycle events, Cyclin A and B, and poly(A) polymerase (PAP). Transcripts for all genes were detected, irrespective of oocyte origin. While differences were not significant in all cases, variations in levels of transcript abundance between the groups were related to developmental competence. In particular, transcripts for GDF-9 were expressed at significantly higher levels in oocytes recovered at the LH peak and matured in vitro than in those matured in vivo. The observations with GDF-9 are interesting as this gene is believed to be essential for normal folliculogenesis and may be important in the regulation of early follicle and oocyte growth. In conclusion, the results of this study demonstrate differences in the relative mRNA abundance of several developmentally important gene transcripts in bovine oocytes which may be related to developmental competence.
Collections Ireland -> University College Dublin -> PubMed

Full list of authors on original publication

Maurice P Boland, Julio de la Fuente, Belen Pintado, Dimitrios Rizos, Alfonso Gutierrez-Adan, Patrick Lonergan

Experts in our system

1
M P Boland
University College Dublin
Total Publications: 103
 
2
D Rizos
University College Dublin
Total Publications: 42
 
3
Alfonso Gutierrez-Adan
University College Dublin
Total Publications: 9
 
4
P. Lonergan
University College Dublin
Total Publications: 190