OK, this is really cool. We knew the nucleus had to be organized into compartments with particular chromosomes taking up particular regions. Now, using an elegant new technique, Rao et al. in a collaboration between the Center for Genome Architecture at Baylor College of Medicine, Rice University in Houston, Texas, and the Broad Institute in Cambridge, Massachusetts, have mapped which bits of DNA are close to each other, or nearest neighbors in the nucleus. The research, reported on in The Scientist, was published in the journal Cell.

They have found that the DNA is neatly packaged in sub-compartments, domains, and loops. There is a code that specifies where the DNA is to be looped, and it’s cell type-dependent. The loops bring regulatory control elements together.

The level of organization is extreme. The video above, clever and informative, uses the analogy of origami, with the DNA carefully folded in on itself. I can understand the analogy, given that it’s a three-dimensional packing problem for DNA. But I would say it’s more like directories, subdirectories, and folder specifications in computers — the path to the information needed. Evolve that!