As the name infers, “junk DNA” has long been considered to be DNA with no biological significance other than as a filler between genes. Recent advances however have overturned these prior beliefs, as scientists now understand that the regions between genes are necessary for a number of vital functions.
Mutations within these regions of “junk DNA” can inhibit development of humans in all stages of life, from prenatal to old age. Until now, finding these indirect regulatory regions of DNA has been elusive. Scientists from the Technical University of Munich (TUM) and Max Planck Institute (MPI) have teamed together to develop a method that is now able to find these non-gene encoding regions that have such extensive influence over active genes.
Genes within our DNA possess extensive assembly instructions, similar to a computer language, for putting together the proteins that go on to form complicated structures within our body; structures that serve a wide variety of essential bodily functions. In order to make sure that every protein completes its task at the correct time, and in the correct place, the activation of the corresponding genes must be tightly controlled. The processes that ensure both the genes and proteins are synchronized are extensive and complex, involving a variety of different feedback mechanisms.
Prof. Patrick Cramer, head of Molecular Biology at MPI, states that regulatory regions of DNA are essential for human development, the immune response and tissue preservation, and also play a critical role in the prevention and management of various diseases. For instance, those patients who have been diagnosed with cancer or heart diseases exhibit a number of mutations in these regulatory DNA regions.
In order to move from gene to protein, DNA must first be encoded into RNA. Unfortunately, RNA is usually short lived, and so it is very hard to isolate these molecules in order to examine which genes are responsible for which proteins. They have been elusive and difficult to find, until now. Researchers supplied cells with a “dummy molecule” that served as an anchor to cells. The cells absorbed these dummy molecules into their RNA during the course of protein synthesis. By later “fishing out” these anchors, the researchers were able to identify the transient RNA molecules that they were attached to, and thus examine them.
Now, researchers will be able to identify exactly how non-coding, regulatory regions of DNA influence coding regions of DNA, and how this coding DNA then synthesizes proteins, Of particular significance is the ability to now examine the regulatory frameworks that take place in controlling the amount of protein synthesized from the DNA level.
Future scientists will now be able to identify the “molecular switches” that control the synthesis of different proteins, which will play particular significance in examining how proteins are synthesized to combat disease. The potential implications of such knowledge could be endless. Already the researchers have planned a future study to apply their technique to blood cells to understand how HIV infection progresses at a DNA level.
Study Source: Science