Yu Xueping, Lin Jimmy, Zack Donald J, Qian Jiang
Wilmer Institute, Johns Hopkins University School of Medicine, Maumenee Building 844, 600 N. Wolfe Street, Baltimore, MD 21287, USA.
Nucleic Acids Res. 2006;34(17):4925-36. doi: 10.1093/nar/gkl595. Epub 2006 Sep 18.
Tissue-specific gene expression is generally regulated by more than a single transcription factor (TF). Multiple TFs work in concert to achieve tissue specificity. In order to explore these complex TF interaction networks, we performed a large-scale analysis of TF interactions for 30 human tissues. We first identified tissue-specific genes for 30 tissues based on gene expression databases. We then evaluated the relationships between TFs using the relative position and co-occurrence of their binding sites in the promoters of tissue-specific genes. The predicted TF-TF interactions were validated by both known protein-protein interactions and co-expression of their target genes. We found that our predictions are enriched in known protein-protein interactions (>80 times that of random expectation). In addition, we found that the target genes show the highest co-expression in the tissue of interest. Our findings demonstrate that non-tissue specific TFs play a large role in regulation of tissue-specific genes. Furthermore, they show that individual TFs can contribute to tissue specificity in different tissues by interacting with distinct TF partners. Lastly, we identified several tissue-specific TF clusters that may play important roles in tissue-specific gene regulation.
组织特异性基因表达通常由不止一个转录因子(TF)调控。多个转录因子协同作用以实现组织特异性。为了探索这些复杂的转录因子相互作用网络,我们对30种人体组织的转录因子相互作用进行了大规模分析。我们首先根据基因表达数据库确定了30种组织的组织特异性基因。然后,我们利用转录因子结合位点在组织特异性基因启动子中的相对位置和共现情况来评估它们之间的关系。通过已知的蛋白质-蛋白质相互作用及其靶基因的共表达对预测的转录因子-转录因子相互作用进行了验证。我们发现我们的预测在已知的蛋白质-蛋白质相互作用中得到了富集(比随机预期高80倍以上)。此外,我们发现靶基因在感兴趣的组织中显示出最高的共表达。我们的研究结果表明,非组织特异性转录因子在组织特异性基因的调控中起很大作用。此外,研究结果还表明,单个转录因子可通过与不同的转录因子伙伴相互作用,在不同组织中促成组织特异性。最后,我们鉴定了几个可能在组织特异性基因调控中发挥重要作用的组织特异性转录因子簇。