The fleeting nature of these weird little knots may also explain why it's been so hard to nail them down, Christ added. 'It seems likely that they are there to help switch genes on or off, and to affect whether a gene is actively read or not,' Zeraati said. This coming and going, he added, hints at the function of the structures. 'What excited us most is that we could see the green spots-the i-motifs-appearing and disappearing over time, so we know that they are forming, dissolving and forming again,' explained Mahdi Zeraati, another study author, who is also with the Garvan Institute. The team tracked the i-motif structures using fluorescence, which highlighted the i-motif DNA structures as green dots. Related: Atacama 'Alien' Skeleton Mystery Revealed With DNA Analysis Importantly, the molecular sliver didn't recognize double-helix-shaped DNA or a similar four-stranded 'G-quadruplex' shape. They took a tiny fragment of an antibody molecule that found and fastened itself to i-motif structures. The researchers used a fine-tuned antibody tool to track down the strange structures and confirm their existence in living cells. This structure arises due to the interaction (hydrogen bonding of base pairs) between the. ' Like Christ, Dinger is an associate professor at the Garvan Institute. The double-helix is the three dimensional structure of a DNA molecule. 'This is very different from a double helix, where 'letters' on opposite strands recognize each other, and where Cs bind to Gs. 'In the knot structure, C letters on the same strand of DNA bind to each other,' said research co-lead Marcel Dinger in the statement. These shapes, researchers think, could affect the way genetic instructions are recognized within the body. 'This new research reminds us that totally different DNA structures exist-and could well be important for our cells.' Related: Sailor killed at Pearl Harbor, identified using DNA, will be laid to rest 'When most of us think of DNA, we think of the double helix,' Daniel Christ, an associate professor at the Garvan Institute of Medical Research in Australia, who co-led the research, said in a statement. But scientists have previously observed short lengths of DNA in different shapes. In 1953, James Watson and Francis Crick discovered the now-famous 'double helix' DNA structure.

Coded into letters-A, C, G and T-these instructions govern the way our bodies look and the way they work. Our cells carry key genetic instructions for growth and functioning in the form of DNA. National Human Genome Research Institute/Handout/Reuters Now, scientists have found a four-stranded twisted 'knot' structure in human cell lines. An artist's impression shows the famous double-helix DNA structure.

Double helix dna