How do you make a Cajal body or superenhancer and what do they have in common?

在哺乳动物细胞核中，染色质采用复杂的三维形状，涉及染色体间和染色体内的接触。这些联系是如何建立和执行的尚不清楚。当染色质从细胞中分离出来时，大部分物质是RNA和与之相关的蛋白质。这种RNA的作用在很大程度上仍未被描述，但越来越多的影响染色质拓扑结构的蛋白质（如CTCF）被证明与RNA相关。因此，RNA可能在染色质结构中发挥关键作用并影响其活性。Cajal小体是细胞核中染色体内接触发生的区域的一个例子，将特定的基因和蛋白质集合在一起，这些基因和蛋白质可以有效地转录和加工由这些基因产生的RNA。染色质接触的第二个例子涉及超增强子，它与多个目标基因启动子形成环，调节它们的转录。我们已经发现了一种连接Cajal小体和超增强子活性并结合RNA、染色质和CTCF的蛋白质。我们的目标是测试该蛋白是否形成RNA：蛋白质网络的一部分，该网络驱动细胞中染色质相互作用，并通过RNA聚合酶II的募集确保靶基因的最佳转录。

Chromatin adopts a complex 3 dimensional shape in the mammalian nucleus which involves inter and intra-chromosomal contacts. How these contacts are made and enforced is not clear. When chromatin is isolated from cells, a large proportion of the material is RNA and proteins which associate with it. The role of this RNA remains largely uncharacterised, yet increasingly proteins which influence chromatin topology such as CTCF are being shown to associate with RNA. Therefore RNA is likely to play a key role in chromatin architecture and influence its activity. The Cajal body is an example of a region in the nucleus where intra chromosomal contacts occur, bringing together a specific collection of genes and the proteins which allow efficient transcription and processing of the RNA produced form those genes. A second example of chromatin contacts involves superenhancers which form loops with multiple target gene promoters, regulating their transcription. We have identified a protein which connects both Cajal body and superenhancer activities and binds RNA, chromatin and CTCF. We aim to test whether this protein forms part of an RNA:protein network which drives chromatin interactions in cells and ensures optimal transcription of target genes by recruitment of RNA polymerase II.