Deoxyribonucleic acid (DNA) contains the information necessary for the production of proteins, molecules which allow a cell to perform all of its functions - grow, divide and carry out specific roles within an organism. This information is found within separate units of the DNA called genes. A gene is simply a stretch of DNA encoding the data for one protein. A large enzyme called RNA polymerase "reads" a gene to direct the production of the protein.
Because many proteins are required for the function of an organism, there is a lot of DNA within a single cell. In fact, if you stretch out the DNA from one cell, it would be about 2 metres long! How can this possibly fit inside a structure that is so small we need a powerful microscope to see it? Well, organisms have evolved an extremely efficient DNA packaging system which is analogous to the way a very long string can be wound into a small, tight ball. DNA is coiled very tightly around a group proteins called histones into a structure called a nucleosome. Nucleosomes are in turn packaged even more tightly into a more complicated structure called chromatin.
This ingenious solution has some drawbacks, however. One of the most challenging is that because the DNA is so tightly packed, RNA polymerase has trouble reading it, especially since it is constantly running into nucleosomes.
My research is focussed on understanding how RNA polymerase overcomes the obstacles posed by nucleosomes and the overall chromatin architecture. More specifically, I study the role of histone chaperones, proteins which bind histones and can temporarily remove them from DNA to allow the passage of RNA polymerase and hence protein production. This knowledge is important, because some human diseases result from defects which prevent RNA polymerase moving efficiently through chromatin and nucleosomes.
