Bacterial DNA is symmetrical and can be read either forwards or backwards

DNA is basically a software code for the living organisms. It is constantly read and various processes are performed according to that encoded information. It is a good system and we’ve known about it for quite some time, but there is still a lot about it that we don’t know. 

For example, scientists at the University of Birmingham have just found that bacterial DNA is symmetrical and can be read either forwards or backwards.

New study showed that bacterial DNA is symmetrical and can be read either way. Human DNA might be like that as well. Image credit: Erick rumualdo bustos ortega via Wikimedia (CC BY-SA 3.0)

Strands of DNA are divided into sections with each containing information about a specific process. These sections need to be read constantly for these processes to be performed. Of course, naturally, that reading process needs to be very precise. DNA strands have signposts marking the beginning of each section – those have been known to science since the 1960s. Scientists believed that the very existence of those signposts means that separate sections of the DNA can only be read in a single direction. However, now this understanding is changing, because researchers discovered that at least in bacteria DNA can be read to either direction.

Researchers found that in single cell organisms those signposts are actually symmetrical. This means that the DNA code can be read in either direction and scientists believe that it is a sign of a whole new level of regulating genes that needs meticulous research. So far they cannot even say why two-directional reading would be necessary, although they are speculating that this arrangement allows avoiding reading ‘collisions’ with other sequences. In other words, this makes for a more efficient DNA reading system.

This current research is focusing on single cell organisms like bacteria. However, researchers believe that similar symmetrical signposts can be found in DNA in other organisms as well, including humans. This would be a hugely important discovery, changing our understanding of how DNA is read in various organisms. This could even have serious implications on treatment of some genetic disorders.

Professor David Grainger, lead author of the study, said: “Understanding how genes are read is fundamental to many branches of biotechnology. Lots of medicines, for example, are dependent on being able to control how genes are read, so it’s important to fully understand how these signals work, and how we can use that knowledge to improve healthcare”.

DNA was discovered in the 1950s and it has been researched ever since. There is still a lot about it that we do not know and it will be important to improve our knowledge before we can treat some genetic disorders. Hopefully studies like this will reveal the secret how cells read DNA and apply information that is encoded in it.

 

Source: University of Birmingham