Research for Module 4 DNA Modules showing Liquid Crystal Phases

A microscope image showing that a solution of tiny DNA molecules has formed a liquid-crystal phase. The DNA molecules pair to form DNA double helices, which, in turn, stack end-to-end to make rod-shaped aggregates that orient parallel to one another. Image by Michi Nakata, University of Colorado. 

A team led by the University of Colorado at Boulder and the University of Milan has discovered some unexpected forms of liquid crystals of ultrashort DNA molecules immersed in water, providing a new scenario for a key step in the emergence of life on Earth.

Liquid crystals - organic materials related to soap that exhibit both solid and liquid properties - are commonly used for information displays in computers, flat-panel televisions, cell phones, calculators and watches. Most liquid crystal phase molecules are rod-shaped and have the ability to spontaneously form large domains of a common orientation, which makes them particularly sensitive to stimuli like changes in temperature or applied voltage.

CU-Boulder physics Professor Noel Clark said "We found that even tiny fragments of double helix DNA can spontaneously self-assemble into columns that contain many molecules. Our vision is that from the collection of ancient molecules, short RNA pieces or some structurally related precursor emerged as the molecular fragments most capable of condensing into liquid crystal droplets, selectively developing into long molecules."