Regulation of the bovine oviductal fluid proteome
Résumé
Our objective was to investigate the regulation of the proteome in the bovine oviductal fluid according to the stage of the oestrous cycle, to the side relative to ovulation and to local concentrations of steroid hormones. Luminal fluid samples from both oviducts were collected at four stages of the oestrous cycle: pre-ovulatory (Pre-ov), post-ovulatory (Post-ov), mid- and late luteal phases from adult cyclic cows (18-25 cows/stage). The proteomes were assessed by nanoLC-MS/MS and quantified by label free method. A total of 482 proteins were identified including a limited number specific to one stage or one side. Proportions of differentially abundant proteins fluctuated from 10 to 24% between sides at one stage and from 4 to 20% among stages in a given side of ovulation. In oviductal fluids ipsilateral to ovulation, Annexin A1 was the most abundant protein at Pre-ov compared to Post-ov while numerous heat shock proteins were more abundant at Post-ov compared to Pre-ov. Among differentially abundant proteins, seven tended to be correlated with intra-oviductal concentrations of progesterone. A wide range of biological processes was evidenced for differentially abundant proteins, among which metabolic and cellular processes were predominant. This work identifies numerous new candidate proteins potentially interacting with the oocyte, spermatozoa and embryo to modulate fertilization and early embryo development.