Nuclear progestin receptor (Pgr) knockouts resulted in subfertility in male tilapia (Oreochromis niloticus)
Nuclear progestin receptor (Pgr) knockouts resulted in subfertility in male tilapia (Oreochromis niloticus)
复制标题
核孕激素受体 (Pgr) 敲除导致雄性罗非鱼 (Oreochromis niloticus) 生育力低下
DOI：
10.1016/j.jsbmb.2018.04.011
复制
发表时间：
2018-09-01
影响因子：
4.1
通讯作者：
Wang, Deshou
中科院分区：
文献类型：
--
作者：
Fang, Xuelian;Wu, Limin;Wang, Deshou
17 α， 20 β -二羟基-4-孕激素-3- 1 （DHP）可能部分通过激活核受体（Pgr）在精子发生、精子成熟和精子形成过程中起关键作用。然而，没有直接证据证明DHP在鱼类精子发生中的作用。为了进一步阐明DHP在硬鱼中的作用，我们在XY尼罗罗非鱼（Oreochromis niloticus）中产生了pgr纯合突变系。与正常睾丸相比，Pgr基因突变导致睾丸更小、更薄，GSI更低。Pgr基因敲除导致生精囊肿排列不规则，精子数量下降，精子活力下降。精母细胞和精子明显减少，PCNA和Ph3染色进一步证实了这一点。Real-time PCR分析显示，pgr基因突变导致激素生成相关基因cyp17 α、cyp11b2、StAR、scc、20 β - hsd和sf1显著上调，fshb、fshr、oct4、sycp3、cdk1、prm、cyclinB1、cyclinB2和cdc25基因下调。免疫组化和Western blotting实验显示，pgr -/-睾丸中Cyp17a1、Cyp17a2和cyp11b2的表达显著升高。EIA测定显示，pgr(-/-) XY鱼体内11-KT水平明显升高。pgr(-/-) XY鱼与野生型XX鱼杂交，后代死亡率显著提高。TUNEL染色增加，凋亡制造基因（bax）表达增强。综上所述，我们的数据表明，dhp通过pgr激活的生理对XY罗非鱼的繁殖至关重要。
It was documented that 17 alpha, 20 beta-dihydroxy-4-pregnen-3-one (DHP), a fish specific progestin, might play critical roles in spermatogenesis, sperm maturation and spermiation partially through activating nuclear receptor (Pgr). However, no direct evidence is available to demonstrate the functions of DHP in fish spermatogenesis. To further elucidate the roles of DHP in teleosts, we generated a pgr homozygous mutant line in XY Nile tilapia (Oreochromis niloticus). Pgr gene mutation resulted in the development of a smaller, thinner testis and a lower GSI compared with normal testis. Pgr gene knockout led to irregular arrangement of spermatogenic cysts, decline of sperm count and sperm motility. Significant decrease of spermatocytes and spermatozoa was observed, which was further proved by the PCNA and Ph3 staining. Real-time PCR analysis demonstrated that mutation of pgr gene resulted in a significant up-regulation of steroidogenesis-related genes of cyp17 alpha, cyp11b2, StAR, scc, 20 beta-HSD, and sf1, and down-regulation of fshb, fshr, oct4, sycp3, cdk1, prm, cyclinB1, cyclinB2 and cdc25 genes Furthermore, both Immunohistochemistry and Western blotting experiments revealed a remarkable increase of Cyp17a1, Cyp17a2 and Cyp11b2 expressions in the pgr -/- testis. EIA measurement showed that an evident increase of 11-KT level was found in the pgr(-/-) XY fish. There was a significant increase in the mortality of offspring when crossing pgr(-/-) XY fish with wild type XX fish. Increased TUNEL staining and enhanced apoptosis maker gene (bax) expressions were also observed. Taken together, our data suggested that DHP-activated physiology via pgr is crucial for the fertility in the XY tilapia.