Steroid signaling in mature follicles is important for Drosophila ovulation
Steroid signaling in mature follicles is important for Drosophila ovulation
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DOI：
10.1073/pnas.1614383114
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发表时间：
2017-01-24
影响因子：
11.1
通讯作者：
Sun, Jianjun
中科院分区：
文献类型：
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作者：
Knapp, Elizabeth;Sun, Jianjun
尽管蜕皮类固醇信号传导调节卵子发生的多个步骤，但尚不清楚它是否调节果蝇排卵，这是一个涉及基质金属蛋白酶依赖性卵泡破裂的过程。在这项研究中，我们证明了蜕皮类固醇信号在成熟卵泡细胞中发挥作用来控制排卵。此外，敲低遮荫（shd）（编码将蜕皮激素（E）转化为活性更高的20-羟基蜕皮激素（20E）的单加氧酶，特别是在成熟卵泡细胞中），可以阻止卵泡破裂，而这是通过shd或外源20E的异位表达来挽救的。此外，成熟卵泡细胞中蜕皮激素受体（EcR）的破坏模拟了shd敲低缺陷，这种缺陷可以被EcR.B2的异位表达逆转，但不能被EcR逆转。 A 或 EcR.B1 同工型。此外，我们还发现，蜕皮类固醇信号传导对于基质金属蛋白酶 2 (Mmp2) 的正确激活以及卵泡破裂至关重要。我们的数据强烈表明，排卵前卵泡细胞中产生的 20E 会激活 EcR.B2，使成熟卵泡对神经元排卵刺激做出反应，从而为果蝇排卵中的类固醇信号传导提供机制见解。
Although ecdysteroid signaling regulates multiple steps in oogenesis, it is not known whether it regulates Drosophila ovulation, a process involving a matrix metalloproteinase-dependent follicle rupture. In this study, we demonstrated that ecdysteroid signaling is operating in mature follicle cells to control ovulation. Moreover, knocking down shade (shd), encoding the monooxygenase that converts ecdysone (E) to the more active 20-hydroxyecdysone (20E), specifically in mature follicle cells, blocked follicle rupture, which was rescued by ectopic expression of shd or exogenous 20E. In addition, disruption of the Ecdysone receptor (EcR) in mature follicle cells mimicked shd-knockdown defects, which were reversed by ectopic expression of EcR.B2 but not by EcR. A or EcR.B1 isoforms. Furthermore, we showed that ecdysteroid signaling is essential for the proper activation of matrix metalloproteinase 2 (Mmp2) for follicle rupture. Our data strongly suggest that 20E produced in follicle cells before ovulation activates EcR.B2 to prime mature follicles to be responsive to neuronal ovulatory stimuli, thus providing mechanistic insights into steroid signaling in Drosophila ovulation.