Chen Liang, Xin Zhong-Cheng, Li Xin, Tian Long, Yuan Yi-Ming, Liu Gang, Jiang Xue-Jun, Guo Ying-Lu
Andrology Center of Peking University First Hospital, Beijing 100009, China.
Asian J Androl. 2006 Sep;8(5):589-94. doi: 10.1111/j.1745-7262.2006.00178.x. Epub 2006 Jun 5.
To investigate the regulatory function of Cox7a2 on steroidogenesis and the mechanism involved in TM3 mouse Leydig cells.
The cDNA of Cox7a2 was cloned from TM3 mouse Leydig cells. It was subcloned to pDsRed-Express-N1 and transfected back into TM3 mouse Leydig cells for Cox7a2 overexpression by transient gene transfection. Steroidogenesis affected by overexpressed Cox7a2 was studied by ELISA. To elicit the mechanism of this effect, expression of steroidogenic acute regulatory (StAR) protein and reactive oxygen species (ROS) were examined by Western blot and fluorometer, respectively.
The cDNA of Cox7a2 (249 bp) was cloned from Leydig cells and confirmed by DNA sequencing. After constructed pDsRed-Express-N1-Cox7a2 was transfected back into TM3 mouse Leydig cells, Cox7a2 inhibited not only luteinizing hormone (LH)-induced secretion of testosterone but also the expression of StAR protein. At the same time, Cox7a2 increased the activity of ROS in TM3 mouse Leydig cells.
Cox7a2 inhibited LH-induced StAR protein expression, and consequent testosterone production, at least in part, by increasing ROS activity in TM3 mouse Leydig cells.
研究Cox7a2对睾酮生成的调控作用及其在TM3小鼠睾丸间质细胞中的作用机制。
从TM3小鼠睾丸间质细胞中克隆Cox7a2的cDNA。将其亚克隆至pDsRed-Express-N1载体，通过瞬时基因转染再转回到TM3小鼠睾丸间质细胞中以过表达Cox7a2。采用酶联免疫吸附测定法（ELISA）研究过表达Cox7a2对睾酮生成的影响。为探究此效应的机制，分别通过蛋白质免疫印迹法和荧光计检测类固醇生成急性调节蛋白（StAR）和活性氧（ROS）的表达。
从睾丸间质细胞中克隆出Cox7a2的cDNA（249 bp），并经DNA测序确认。构建的pDsRed-Express-N1-Cox7a2转回到TM3小鼠睾丸间质细胞后，Cox7a2不仅抑制促黄体生成素（LH）诱导的睾酮分泌，还抑制StAR蛋白的表达。同时，Cox7a2增加了TM3小鼠睾丸间质细胞中ROS的活性。
Cox7a2至少部分通过增加TM3小鼠睾丸间质细胞中ROS的活性来抑制LH诱导的StAR蛋白表达及随后的睾酮生成。
