Study reveals that bacteria DNA signals can be read either forward or backward

According to recent research from the University of Birmingham, bacteria’s DNA signals have symmetry that allows them to be read either backward or forward, challenging the current understanding of gene transcription.

The DNA code of all living organisms is split into parts that include data about a particular mechanism. Before the data can be used, it must be read. Cells use “signposts” to determine the beginning of each segment, which scientists first discovered in the 1960s.

It has long been believed that these signposts allow genetic sequences to be read in only one direction. The new research, published in Nature Microbiology, demonstrates that symmetrical DNA signposts exist in single-celled species. This means that the DNA code can be read in both directions.

Most of the studies on gene signaling overlook the symmetry, but we think this is incredibly significant and represents a whole new level of regulating genes that has not yet been investigated.”

David Grainger, Study Lead Author and Professor, University of Birmingham

The exact cause for the bidirectional reading is unknown and would take further analysis. One theory being considered by the team is that it assists in avoiding reading “collisions” with other sequences.

Even though the present analysis focused mostly on bacteria, the researchers propose that the signpost symmetry is likely to be observed in animals, humans, and other species as well. The next step in the study will be to look at the phenomenon in yeast cells, which are more similar to human cells.

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.”

David Grainger, Study Lead Author and Professor, University of Birmingham