The linear sequence of bases which make up the genome are not an exact description of the information it encodes. The 3D organisation of the DNA is also crucial in dictating its function.
The human genome is spatially organised inside the nucleus. Although at first we might only think the sequence of DNA is important, the 3D arrangement of DNA is also key to the control of gene expression. DNA is packaged depending on how often it is expressed. Euchromatin is highly expressed and heterochromatin is expressed less. Interactions with regulatory proteins manipulate DNA to bring different sequences together and change gene expression.
Understanding how the 3D organisation of DNA in the nucleus is managed and how it changes over time is key to understanding the expression of the genome at a level beyond that of the DNA sequence alone.
This image was inspired by research by Wendy Bickmore.