Foroughinia Golshan, Fazileh Ali, Eghbalsaied Shahin
Transgenesis Center of Excellence, Isfahan (Khorasgan) Branch, Islamic Azad University, Iran.
Transgenesis Center of Excellence, Isfahan (Khorasgan) Branch, Islamic Azad University, Iran; Department of Animal Science, Isfahan (Khorasgan) Branch, Islamic Azad University, Isfahan, Iran.
Theriogenology. 2017 Mar 15;91:36-43. doi: 10.1016/j.theriogenology.2016.12.023. Epub 2016 Dec 24.
Follicular growth and ovulation of healthy oocytes is a complicated process which is regulated by several endocrine and paracrine factors as well as cross-talk between the oocyte and its surrounding somatic cells. This study compared the expression profile of some candidate genes involved in BMP signaling as well as estrogen and AMPK production in cumulus-oocyte complex (COC) of small and large antral follicles and their associated somatic cell layers in ovaries from ewes with high- and low-antral follicle count (AFC). Expression of GDF9 was increased by increasing the size of antral follicles, while BMP15 expression was decreased by follicular size. It should be noteworthy that transcription of both GDF9 and BMP15 was also detected in the adjacent cellular layers under the follicles. There was a very strong positive correlation between BMP15 and BMPR2 in ovary tissues. Expression of GDF9 was highly correlated with BMP15, BMPR1B, and BMPR2 in large antral follicles. Expression of BMP7 in small antral follicles and BMPR2 in ovary tissues was significantly increased in the high-AFC group. Expression of ESR1 and ESR2 involved in estrogen production as well as PRKAA1 which involved in AMPK production were significantly greater in large antral follicles of high-AFC. There was a very high correlation between Cyp19 and ESR1 in large antral follicles and ovary tissues. Expression of Cyp19 and PRKAA1 were positively correlated with GDF9, BMP15, and BMP7 in large follicles. In conclusion, this study suggests that apart from the BMP signaling, genes involved in AMPK and estrogen production can be pivotal players in ewe's follicular development process. In addition, a strong cross-talk can exist among AMPK, BMP signaling, and estrogen synthesis systems in ewe ovary.
健康卵母细胞的卵泡生长和排卵是一个复杂的过程，受多种内分泌和旁分泌因子以及卵母细胞与其周围体细胞之间的相互作用调控。本研究比较了高、低窦状卵泡计数（AFC）母羊卵巢中大小窦状卵泡及其相关体细胞层的卵丘-卵母细胞复合体（COC）中一些参与骨形态发生蛋白（BMP）信号传导以及雌激素和AMPK产生的候选基因的表达谱。随着窦状卵泡大小的增加，生长分化因子9（GDF9）的表达增加，而BMP15的表达则随卵泡大小而降低。值得注意的是，在卵泡下方的相邻细胞层中也检测到了GDF9和BMP15的转录。卵巢组织中BMP15和骨形态发生蛋白受体2（BMPR2）之间存在非常强的正相关。在大窦状卵泡中，GDF9的表达与BMP15、骨形态发生蛋白受体1B（BMPR1B）和BMPR2高度相关。在高AFC组中，小窦状卵泡中BMP7的表达和卵巢组织中BMPR2的表达显著增加。在高AFC的大窦状卵泡中，参与雌激素产生的雌激素受体1（ESR1）和雌激素受体2（ESR2）以及参与AMPK产生的蛋白激酶AMP激活的催化亚基α1（PRKAA1）的表达显著更高。在大窦状卵泡和卵巢组织中，细胞色素P450家族19亚家族A成员1（Cyp19）和ESR1之间存在非常高的相关性。在大卵泡中，Cyp19和PRKAA1的表达与GDF9、BMP15和BMP7呈正相关。总之，本研究表明，除了BMP信号传导外，参与AMPK和雌激素产生的基因可能是母羊卵泡发育过程中的关键参与者。此外，母羊卵巢中AMPK、BMP信号传导和雌激素合成系统之间可能存在强烈的相互作用。
