College of Veterinary Medicine, Shaanxi Centre of Stem Cells Engineering & Technology, Key Lab for Animal Biotechnology of Agriculture Ministry of China, Northwest A&F University, Yangling, Shaanxi, 712100, China.
J Cell Biochem. 2014 Feb;115(2):232-42. doi: 10.1002/jcb.24655.
miRNAs are expressed in many mammalian cells, acting specific roles in regulating gene expression or mediating special mRNAs cleavage by targeting their 3'-untranslated region (3'UTR). Some miRNAs are essential and important for animal development. However, it is still unclear what the relationship is between miR-34c and mammalian spermatogonial stem cells (SSCs). We found that a conserved microRNA-34c through its target-Nanos2, regulating SSCs' differentiation in mouse. Immunohistochemistry analysis of Nanos2 and miR-34c FISH results revealed the opposite expression trends between them. Seven bioinformatics websites and programs predicted that miR-34c has interaction sites in Nanos2's 3'UTR. Dual-luciferase reporter vector and mutated dual-luciferase reporter vector analysis validated that they are interacted. After transfection miR-34c mimics into mouse SSCs, or miR-34c lentiviral vector in vitro co-cultivation with seminiferous tubules, and Western blot analysis demonstrated that miR-34c over-expression could suppress Nanos2 expression in post-transcription level. Our experiments identified that miR-34c may promote meiosis process by interacting with Nanos2 leading up-regulation of Stra8 in mouse spermatogonial stem cells.
miRNAs 在许多哺乳动物细胞中表达，通过靶向其 3'非翻译区（3'UTR）来特异性调节基因表达或介导特殊 mRNAs 的切割。一些 miRNAs 对动物发育至关重要。然而，miR-34c 与哺乳动物精原干细胞（SSC）之间的关系仍不清楚。我们发现，保守的 microRNA-34c 通过其靶基因-Nanos2，调控小鼠 SSCs 的分化。Nanos2 和 miR-34c FISH 的免疫组织化学分析结果显示它们的表达趋势相反。七个生物信息学网站和程序预测 miR-34c 在 Nanos2 的 3'UTR 中有相互作用位点。双荧光素酶报告载体和突变双荧光素酶报告载体分析验证了它们的相互作用。转染 miR-34c 模拟物进入小鼠 SSCs 后，或 miR-34c 慢病毒载体与生精小管体外共培养后，Western blot 分析表明 miR-34c 过表达可以在转录后水平抑制 Nanos2 的表达。我们的实验表明，miR-34c 可能通过与 Nanos2 相互作用促进减数分裂过程，导致 Stra8 在小鼠精原干细胞中的上调。
