Sox30基因敲除致小鼠睾丸间质细胞增殖异常的研究

Abnormal proliferation of Leydig cells in Sox30 knockout mice

目的探讨Sox30基因敲除对小鼠睾丸间质细胞增殖的影响。方法采用HE染色法观察10周龄Sox30基因野生型(Sox30^(+/+))、杂合型(Sox30^(-/+))及纯合缺失型(Sox30^(-/-))小鼠睾丸组织病理形态;采用免疫组化技术检测睾丸组织中间质细胞特异性表达蛋白3β-HSD的表达水平;采用慢病毒感染及siRNA干扰技术构建Sox30基因过表达及敲低TM3细胞模型,并在此细胞模型基础上分别采用CCK-8法、流式细胞术、RT-qPCR法以及Western blot法检测细胞存活率、细胞周期分布及周期相关基因的mRNA及蛋白表达水平。采用JASPAR数据库预测Sox30与周期相关基因的启动子区结合位点。结果与Sox30^(+/+)和Sox30^(-/+)小鼠比较,HE染色结果显示Sox30^(-/-)小鼠睾丸组织中间质细胞显著增生,同时免疫组化染色发现表达3β-HSD的间质细胞增多。与Vector组相比,Sox30组TM3细胞存活率降低(P<0.05),G1期细胞周期阻滞(P<0.05),同时细胞周期相关基因CyclinD1、Cdk2等mRNA和蛋白表达水平显著降低(P<0.05)。与Sox30-NC组比较,siSox30-3组TM3细胞存活率增加(P<0.05),G1期细胞周期阻滞恢复(P<0.05),同时细胞周期相关基因CyclinD1、Cdk2等mRNA和蛋白表达水平显著恢复(P<0.05)。JASPAR预测发现CyclinD1、Cdk2的启动子区域均存在Sox30蛋白质可能的结合位点。结论Sox30基因敲除可导致小鼠间质细胞增殖异常,CyclinD1和Cdk2可能是Sox30调控细胞周期的重要靶基因。

Objective To investigate the effect of Sox30 gene knockout on the proliferation of mouse Leydig cells. Methods The pathological morphology of the testis of 10-week-old Sox30^(+/+), Sox30^(-/+) and Sox30^(-/-) mice was observed with HE staining. Immunohistochemical assay was adopted to detect the expression level of 3β-HSD in the Leydig cells. The cell models of Sox30 gene overexpression and knockdown were constructed by lentivirus infection and siRNA interference in TM3 cell line, respectively. On the basis of these cell models, CCK-8 assay, flow cytometry, RT-qPCR and Western blotting were used to detect the cell survival rate, cell cycle distribution, and expression of cell cycle-related genes and proteins. The JASPAR database was used to predict the binding sites of Sox30 protein in promoter region of cycle related genes. Results Compared with Sox30^(+/+) and Sox30^(-/+) mice, HE staining indicated that the number of Leydig cells were significantly increased, and immunohistochemical assay showed the expression of 3β-HSD were increased the Leydig cells in the testis tissue of Sox30^(-/-) mice. Compared with the blank vector group, Sox30 overexpression led to the decrease of cell count(P<0.05), cell cycle arrest in G1 phase(P<0.05), and significantly decreased expression of CyclinD1 and Cdk2 at mRNA and protein levels(P<0.05). On the contrary, Sox30 knockdown resulted in opposite phenomena(P<0.05). JASPAR database predicted that Sox30 may bind to the promoter of CyclinD1 and Cdk2. Conclusion Knockout of Sox30 induces abnormal proliferation of Leydig cells in mice. CyclinD1 and Cdk2 may be important downstream targets of Sox30 gene in the regulation of cell cycle in Leydig cells.