In the most recent Science there was A paper published on the 3 dimensional shapes taken by RNA. It's important for their own work of course, but more intriguing is the potential implications on our understanding of the very dawn of life.
RNA is quite an amazing thing, really. It's vital to the functioning of our body and is widely considered to be what the evolution of DNA started from. It can be translated into or from DNA and codes for information like DNA, but it is not a double helix, containing only a single strand. That gives it a remarkable ability to curl up into wonderfully complex 3D shapes:
“RNA is a very floppy molecule that often functions by binding to something else and then radically changing shape,” explains Hashim Al-Hashimi, the Robert L. Kuczkowski Professor of Chemistry and a professor of biophysics at the University of Michigan.
The point of all this? To give us better functioning, more targeted drugs that can use lower doses to achieve the same effect:
Because of the RNA molecule’s mercurial nature, “you can’t really define it as having a single structure,” Al-Hashimi says. “It has many possible orientations, and different orientations are stabilized under different conditions, such as the presence of particular drug molecules.”
A major goal in structural biology and biophysics is to be able to predict not only the complex three-dimensional shapes that RNA assumes (which are dictated by the order of its nucleic acid building blocks), but also the various shapes RNA takes on after binding to other molecules such as proteins and small-molecule drugs
The focus on RNA for these drugs takes place a backdrop of vital importance, everything from HIV to genetic disease has been linked to RNA in recent research:
The recent explosion in vital cellular roles ascribed to RNA, and the growing number of diseases linked to RNA malfunction, makes manipulating RNA a much sought-after goal, researchers say.
RNA performs many of its roles by serving as a switch that changes shape in response to cellular signals, prompting appropriate reactions in response.
The versatile molecule also is essential to retroviruses such as HIV, which have no DNA and instead rely on RNA to both transport and execute genetic instructions for everything the virus needs to invade and hijack its host.
The article makes for fascinating reading, but doesn't delve into some of the other reasons this research can lead us to exciting new ground: RNA folding could help us see our humblest origins. RNA is bandied around as the precursor to DNA not just because of how its used today, but because it's folding would allow it to become it's own catalyst, helping to speed the chemical reactions to speeds needed for life, as well as pass on that orientation in what may have been the seed of heredity, the beginning of life.