by Josh Green
As we should all know from our GCSE’s (and equivalent times that seem so long ago) the very complex molecule called DNA, the full name of which is deoxyribonucleic acid, contains all of the genetic information in all known living organisms. A tremendous amount of research goes into further understanding DNA, and how the information inside expresses itself in all living things, and also goes into how scientists can manipulate DNA for various applications. One way of being able to manipulate DNA is by folding it. A technique called ‘DNA origami’ is an established technique going back to the 1980’s and was first pioneered by Paul Rothemund at the California Institute of Technology.
However, there exists a problem when trying to create 3D structures with DNA. At their current ability, scientists trying to do ‘DNA origami’ have to remove DNA from a cell and manipulate the DNA molecules outside of it. This leads to problems such as having to take DNA out of a system that its suited to and introduces the problem of having to synthetically create chemicals as a result. Tackling this issue, exciting news from the Technical University of Munich (TUM) has come forward. Two TUM researchers, Florian Praetorius and Hendrik Dietz, have managed to come up with a new method which allows for ‘DNA origami’ to be conducted inside the cell.
In ‘DNA origami’ proteins are used to construct the DNA structures. These types of proteins are called ‘staple proteins’. There is a type of protein in nature called TAL effectors and these researchers at TUM have based their staple proteins on the TAL effectors. These specific proteins are used by bacteria to attach onto certain parts of DNA structures which, for example in nature, can nullify a plant’s ability to fight the bacteria off using its own defence mechanisms. Praetorius and Dietz have created a variant of the TAL effectors so that the protein can bind to two separate parts of the DNA structure and effectively act as a staple. Using these newfound staple proteins alongside DNA double strands that have lots of ‘binding states’ the DNA can be manipulated into more and more complex shapes. When these structures have been made, the staple proteins act as anchoring points for other types of proteins and create hybrid structures that leads to the possibility that cells can create all of the components needed to create the hybrid structures and for those structures to form as well without external influence. The researchers were able to see this occur, when using types of environments very similar to real cells, and state that there is a strong probability that this will be able to be seen in real cells as well.
This method could lead to improved research techniques in the field of cell biology and biomedical technology, leading to very positive real-world applications in time.