Abstract：
Spermatogenesis is highly conserved among mammalians, but its gene expression and regulatory profile are not entirely known. As transcription factors (TFs) and miRNAs are crucial for gene expression regulation, identifying genes negatively regulated by miRNAs and positively regulated by TFs in the testis and epididymis can provide a deeper understanding of gene expression and regulatory patterns. To do this, we used expression data coming from RNA-Seq and miRNA-Seq experiments made with biopsies from testicular parenchyma, head of the epididymis, and tail of the epididymis of four Brahman bulls. We identified miRNA differentially expressed (DE) by comparing the three distinct tissues. A co-expression analysis combined with a regulatory impact factor approach identified miRNAs and TFs with regulatory impact over gene expression regulation in the Bos indicus tissues studied. We identified 116 DE miRNAs, 206 miRNAs and 237 TFs with a significant regulatory impact on mRNA patterns in the tissues\' comparisons. bta-miR-196b was the only DE miRNA for all tissue comparisons and it may be a regulator of spermatogenesis through its links with adipogenesis and insulin biosynthesis. DE genes and TFs involved in contrary regulations between the epididymis head and testis parenchyma were associated with spermatogenesis, sexual reproduction, and sperm motility. Our results provide possible mechanisms, governed by the contrary effect of miRNA and TF, leading to the differential expression between the studied tissues. We have demonstrated that our predictions of miRNAs and TFs co-regulations over target DE genes can retrieve known regulatory mechanisms and predict new ones that merit further validation.
摘要：
精子发生在哺乳动物中高度保守，但是它的基因表达和调节谱并不完全清楚。由于转录因子（TFs）和miRNA对基因表达调控至关重要，在睾丸和附睾中识别由miRNA负调控和由TFs正调控的基因可以提供对基因表达和调控模式的更深入的理解。要做到这一点，我们使用了来自RNA-Seq和miRNA-Seq实验的表达数据，这些实验是用睾丸实质的活检进行的，附睾的头,和四个婆罗门公牛附睾的尾巴。我们通过比较三种不同的组织来鉴定差异表达(DE)的miRNA。与调节影响因子方法结合的共表达分析鉴定了在所研究的Bosindicus组织中对基因表达调节具有调节影响的miRNA和TF。我们鉴定出116个DEmiRNAs,206个miRNA和237个TFs，对组织中的mRNA模式有显著的调节作用。bta-miR-196b是所有组织比较中唯一的DEmiRNA，它可能通过与脂肪生成和胰岛素生物合成的联系成为精子发生的调节因子。参与附睾头部和睾丸实质之间相反调节的DE基因和TFs与精子发生有关，有性生殖,和精子活力。我们的结果提供了可能的机制，受miRNA和TF的相反作用支配，导致所研究组织之间的差异表达。我们已经证明，我们对miRNA和TFs共同调控靶DE基因的预测可以检索已知的调控机制，并预测值得进一步验证的新机制。
