Identification of transcription factors and cofactors binding to type 2 diabetes risk variants which modulate allele- and tissue-specific gene expression and phenotypes.

对于2型糖尿病(T2D)，已经确定了超过65个遗传风险基因。大多数变异位于非编码区，这表明调节基因表达的调节变异是疾病风险的主要贡献者。在大多数情况下，在连锁不平衡中存在大量变异的调节变异和处于危险位点的调节基因仍然难以捉摸。此外，大量数据支持对基因表达的组织和等位基因特异性调控，这依赖于转录因子和辅助因子之间的高度调控相互作用，但确切的机制仍不清楚，特别是等位基因特异性基因调控。在这里，我们将通过将我们团队引入的生物信息学策略与监管区域的公共领域表观基因组标记相结合来寻找监管变体。此外，我们将使用一种高效的蛋白质组学方法，鉴定等位基因和组织特异性转录因子和辅因子。通过不同的方法，如报告和DNA结合分析，全基因组表达谱和CRISPR基因组编辑，我们将确认基因对转录活性的依赖调控，近距离和远距离基因调控由识别的因素。最后，将评估疾病特异性表型的调节，如T2D的胰岛素敏感性和胰岛素分泌。我们将揭示TCF7L2基因座的机制，据报道，TCF7L2基因座调节β细胞、肝脏和脂肪组织的T2D表型；并考虑对更多建议调节组织特异性基因表达的基因座进行分析，如FTO或TLE1。我们对风险基因的组织特异性深入分析，从识别调节变异、结合蛋白复合体、调节基因和调节表型，可能指导识别先前未知的个体化干预切入点。

For types 2 diabetes (T2D) more than 65 genetic risk loci have been identified. Most variants are located in noncoding regions, suggesting that regulatory variants modulating gene expression are major contributors to disease risk. Both, regulatory variants and regulated genes at risk loci with numerous variants in linkage disequilibrium remain elusive in most cases. Moreover, numerous data support tissue- and allele-specific regulation of gene expression, which depends on a highly regulated interaction of transcription factors and cofactors, but the precise mechanisms remain elusive in particular for allele-specific gene regulation. Here, we will find regulatory variants by combining a bioinformatics strategy introduced by our group with public domain epigenomic marks of regulatory regions. Moreover, we will identify both, allele- and tissue-specific transcription factors and cofactors, using a highly efficient proteomics methodology. By diverse approaches, such as reporter- and DNA-binding assays, genome-wide expression profiling and CRISPR genome editing, we will confirm genotype dependent modulation of transcriptional activity, nearby and distant gene regulation by the identified factors. Finally, modulation of disease specific phenotypes will be assessed, such as insulin-sensitivity and insulin-secretion for T2D. We will uncover mechanisms at the TCF7L2 locus, reported to modulate T2D phenotypes in beta-cells, liver and adipose-tissue; and consider analysis at further loci suggested to modulate tissue-specific gene expression such as FTO or TLE1. Our tissue-specific in-depth analysis at risk loci, ranging from identification of regulatory variants, binding protein-complexes, regulated genes and modulated phenotypes may guide identification of previously unknown entry points for personalized intervention.