This Article Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Sayasith, K. Articles by Sirois, J. Search for Related Content PubMed PubMed Citation Articles by Sayasith, K. Articles by Sirois, J.

Molecular characterization of tumor necrosis -induced protein 6 and its human chorionic gonadotropin-dependent induction in theca and mural granulosa cells of equine preovulatory follicles

Centre de Recherche en Reproduction Animale and Département de Biomédecine Vétérinaire and ¹ Département de Pathologie et Microbiologie, Faculté de Médecine Vétérinaire, Université de Montréal, 3200 Sicotte, Saint-Hyacinthe, Québec, Canada J2S 7C6

Correspondence should be addressed to K Sayasith; Email: k.sayasith{at}umontreal.ca

The preovulatory rise in gonadotropins causes an expansion of the cumulus–oocyte complex, a process requiring the induction of several genes. The objectives of this study were to clone the equine tumor necrosis factor -induced protein 6 (TNFAIP6), and investigate its regulation in equine follicles during human chorionic gonadotropin (hCG)-induced ovulation. The isolation of the equine TNFAIP6 cDNA revealed that it contains an open reading frame of 834 bp (including the stop codon), encoding a predicted 277 amino acid protein that is highly similar (91–93% identity) to known mammalian homologs. The regulation of TNFAIP6 mRNA was studied in equine follicles isolated during estrus between 0 and 39 h post-hCG and in corpora lutea (CL) obtained on day 8 of the estrous cycle. Results from semi-quantitative RT-PCR/Southern blot showed that levels of TNFAIP6 mRNA were low in follicles obtained at 0 h, increased at 12 h, returned to basal levels at 24 h, and increased again at 36 h post-hCG (P<0.05). Levels of TNFAIP6 transcripts were relatively moderate in CL, but low in non-ovarian tissues tested. Analyses performed with isolated preparations of theca and granulosa cells indicated that TNFAIP6 mRNA was regulated in both layers, with a maximal induction obtained 33–36 h post-hCG (P<0.05). Immunohistochemical staining of sections of equine follicles isolated at 0 and 33 h post-hCG confirmed the induction of TNFAIP6 protein in both cell types after hCG treatment. Thus, the present study describes for the first time the gonadotropin-dependent regulation of follicular TNFAIP6 during the ovulation in a monoovulatory species. The biphasic induction of TNFAIP6 in equine theca and granulosa cells differs from the pattern observed in rodents, suggesting a distinct control of gene expression in this monoovulatory species.

This article has been cited by other articles:

				D. Haouzi, S. Assou, K. Mahmoud, B. Hedon, J. De Vos, D. Dewailly, and S. Hamamah LH/hCGR gene expression in human cumulus cells is linked to the expression of the extracellular matrix modifying gene TNFAIP6 and to serum estradiol levels on day of hCG administration Hum. Reprod., November 1, 2009; 24(11): 2868 - 2878. [Abstract] [Full Text] [PDF]

				K. Sayasith, N. Bouchard, M. Dore, and J. Sirois Regulation of Bovine Tumor Necrosis Factor-{alpha}-Induced Protein 6 in Ovarian Follicles during the Ovulatory Process and Promoter Activation in Granulosa Cells Endocrinology, December 1, 2008; 149(12): 6213 - 6225. [Abstract] [Full Text] [PDF]

				E. Nagyova, A. Camaioni, R. Prochazka, A. J. Day, and A. Salustri Synthesis of Tumor Necrosis Factor Alpha-Induced Protein 6 in Porcine Preovulatory Follicles: A Study with A38 Antibody Biol Reprod, May 1, 2008; 78(5): 903 - 909. [Abstract] [Full Text] [PDF]