3-D Imaging of DNA Migration

At the Lawrence Berkeley National Laboratory, scientists have been able to document the movement and reorganization of genetic material that takes place within a cell through 3-D visualizations. In the image below, researchers developed a 3-D reconstruction of mouse olfactory cells through X-ray imaging tools. The importance of this discovery allows for easier understanding of patterning and reorganization of chromatin within in the cell's nucleus. By understanding how the chromatin is organized within the nucleus, it helps to determine its relation the the cell's specialization in terms of activated or silenced genes.

The process of the 3-D visualization is performed through a powerful X-ray microscope at Berkeley Lab's Advanced Light Source (ALS). Researchers capture images of the cells of interest at different maturity stages as the cell becomes more specialized for its specific function. This process, known as "differentiation", uses different angles of 2-D images to calculate the 3-D reconstruction of the chromatin formation. 

The benefits of the 3-D visualization of the chromatin was not having to chemically treat the cell in order to observe the change in the nucleus. Because chromatin is very sensitive, chemical stains had to be used to indirectly image the cell, assuming the stain was evenly distributed. According to Carolyn Larabell, a faculty scientist at Berkeley Lab, originally hypothesized that chromatin exist as a series of disconnected islands. However, through the 3-D visualization, it was determined that chromatin was all connected and packed within the nucleus. Larabell hopes that new insight into gene expression can be made, especially with their current study of mice olfactory genes.

Through using the mouse olfactory genes as a model for studying, researchers hope to target how the gene expression works within Alzheimer's disease. The disease itself attacks the brain's nerve cells in which can cause a loss in senses such as smell. By using the 3-D imaging technique, scientists can understand the connection of the gene expression to the olfactory nerve cells. By using this study as a precursor, scientists can hopefully use this technique to determine cures for other diseases that attack nerves cells. This study is very important in medicine and cell research because it allows scientists how diseases and disorders are related to gene expression. By targeting which expressed gene causes a disease, drugs can be created that can silence the gene expression, thus leading to a very large breakthrough in medicine.