Spatiotemporal expression profile of a putative β propeller WDR72 in laying hens

Abstract

The purpose of this study is to characterize the expression profile of a novel gene WDR72 in laying hens. Sixty-week old Hy-line Brown layers with similar laying sequence, egg weight, and shell strength, were selected and divided into 5 groups. The oviduct segments, such as magnum, white isthmus, and uterus, were sampled from each group of hens which were killed at 3 h post-oviposition (3 h P.O.), 4.15-4.5 h P.O., 8.5-9 h P.O., 12 h P.O. and 18 h P.O., respectively. To the 8.5-9 h P.O. hens, additional organs were also sampled besides oviduct tissues. Moreover, another group of hens with weak shell strength were selected and their oviduct segments were sampled at 12 h P.O. Then the expression profile of WDR72 was analyzed using real-time quantitative RT-PCR. The results showed as follows. (1) WDR72 transcripts specifically distributed in parts of organs investigated. At 8.5-9 h P.O., WDR72 appeared to be much more abundantly expressed in hens' oviduct sections, then followed in turn by brain, kidney, lung, glandular stomach and spleen. However, there were almost no WDR72 transcripts expressed in pectoral muscle, liver, heart and jejunum. (2) During the process of an "egg" passing through an oviduct, the expression of WDR72 in the magnum was greatly superior to that in the other two oviduct segments at 3 h P.O., 8.5-9 h P.O., and 12 h P.O.; while it was white isthmus in which WDR72 transcript levels were the highest at 4.15-4.5 h P.O. and 18 h P.O. (3) To any oviduct segment, not only uterus but also magnum and white isthmus, the expression of WDR72 in which was significantly up-regulated at the stages of active calcification. (4) WDR72 transcript levels in any oviduct segments of strong-shell hens were significantly higher than that of weak-shell layers (P < 0.01), which arose the possibility that WDR72 was positively associated with chicken eggshell strength. In conclusion, the expression profile of WDR72 gene in laying hens has been characterized, which would facilitate to further probe into its functions.

Expression of Nerve Growth Factor (NGF) and Its Receptors TrkA and p75 in the Reproductive Organs of Laying Hens

“…The ovum is captured by the infundibulum, and after approximately 15 min, the ovum moves through the infundibulum and enters the magnum. It takes 3-4 h for an ovum to pass through the magnum, where the albumen proteins are secreted, and 1-2 h to move down the white isthmus, where the bilayered membranes are built around the ''egg'' (Liu and Li, 2013). Tubal liquid is a complex mixture composed of plasma and secreting protein (Verhage et al, 1988;Willis et al, 1994).…”