目的:研究顶体相关蛋白Dkkl1在小鼠睾丸组织发育过程中的表达特征。方法将4d、9d、18d、35d、54d和6月龄小鼠睾丸组织cDNA探针与Affymetrix全基因组芯片进行杂交,筛选出差异表达的Dkkl1基因。采用RT-PCR方法检测Dkkl1基因在小鼠不同日龄和不同组织中的表达情况,采用免疫组化方法检测Dkkl1蛋白在小鼠睾丸组织中的定位。结果对Affymetrix全基因组芯片杂交结果分析后,筛选得到1个差异表达杂交点,通过在NCBI网站与小鼠全基因组序列Blast分析可知该差异表达基因是Dkkl1基因。RT-PCR结果表明Dkkl1 mRNA呈小鼠睾丸特异性表达,在出生31d小鼠睾丸开始高表达,在成年前达到高峰。Dkkl1蛋白主要定位在睾丸精母细胞和圆形精子细胞。结论 Dkkl1基因存在发育的表达调控,为小鼠年龄依赖性表达基因,其表达与小鼠精子发生的过程有很强的一致性,且具有睾丸特异性表达的特征,因此我们推测该基因可能在精子发生中具有关键作用。
Objective To investigate the expression and distribution of Dickkopf-Like1 Protein (Dkkl1) in the development of mouse testis.Methods Testes cDNA samples from Balb/C mice in different postnatal days were hybridized with mouse whole genome affymetrix chip to screen the spermatogenesis-ralated genes. The characteristics of the selected genes were analyzed by various bioinformatics tools. The mRNA expression of Dkkl1 at different stages of testis development and different tissues in mouse were detected by RT-PCR. The protein localization of Dkkl1 in mouse testis was assessed by immunohistochemistry.Results By analyzing the gene chip signals of mice testis aged at 4, 9, 18, 35, 54 d and 6 months, Dkkl1 was identified with a differential expression in the developmental stages of testis. RT-PCR analysis showed the expression of Dkkl1 mRNA was firstly detected on 18d testis tissue sample and gradually upregulated during the testis developing to the adult stage. The Dkkl1 protein was predominantly located in spermatocytes and round spermatids in mouse testis.Conclusion The expression of Dkkl1 is gradually upregulated during the development of mouse testis and corresponds to the mouse spermatogenesis. It may play an critical role in male mammalian spermatogenesis.