Reality is full of surprises. Even at the most basic level of our biology, our DNA, there seems to be an engine of random activity as the seed of creation.
A real-time video of DNA being coppied below (2017 research) shows a component of this chaos in creativity. We, as all self-organizing systems do due to entropy, tend toward states of resonance and harmony. I call this trait of harmonizing randomness, our randomoniusness. I think this is what others call life force.
Almost all life on Earth is based on DNA being copied, or replicated. Now for the first time scientists have been able to watch the replication of a single DNA molecule, with some surprising findings. For one thing, there’s a lot more randomness at work than has been thought.
Here’s proof of how far we’ve come in science – in a world-first [this was in 2017 – Xeno], researchers have recorded up-close footage of a single DNA molecule replicating itself, and it’s raising questions about how we assumed the process played out.
The real-time footage has revealed that this fundamental part of life incorporates an unexpected amount of ‘randomness’, and it could force a major rethink into how genetic replication occurs without mutations. ..
The DNA double helix consists of two intertwining strands of genetic material made up of four different bases – guanine, thymine, cytosine, and adenine (G, T, C and A).
Replication occurs when an enzyme called helicase unwinds and unzips the double helix into two single strands. A second enzyme called primase attaches a ‘primer’ to each of these unravelled strands, and a third enzyme called DNA polymerase attaches at this primer, and adds additional bases to form a whole new double helix.
… Scientists have long assumed that the DNA polymerases on the leading and lagging strands somehow coordinate with each other throughout the replication process, so that one does not get ahead of the other during the unravelling process and cause mutations.
But this new footage reveals that there’s no coordination at play here at all – somehow, each strand acts independently of the other, and still results in a perfect match each time. The team extracted single DNA molecules from E. coli bacteria, and observed them on a glass slide. They then applied a dye that would stick to a completed double helix, but not a single strand, which means they could follow the progress of one double helix as it formed two new double helices.
While bacterial DNA and human DNA are different, they both use the same replication process, so the footage can reveal a lot about what goes on in our own bodies.
The team found that on average, the speed at which the two strands replicated was about equal, but throughout the process, there were surprising stops and starts as they acted like two separate entities on their own timelines. Sometimes the lagging strand stopped synthesising, but the leading strand continued to grow. Other times, one strand could start replicating at 10 times its regular speed – and for seemingly no reason.
“We’ve shown that there is no coordination between the strands. They are completely autonomous,” Kowalczykowski says.
The researchers also found that because of this lack of coordination, the DNA double helix has had to incorporate a ‘dead man’s switch’, which would kick in and stop the helicase from unzipping any further so that the polymerase can catch up.
The question now is that if these two strands “function independently” as this footage suggests, how does the unravelling double helix know how to keep things on track and minimise mutations by hitting the breaks or speeding up at the right time?
Hopefully that’s something more real-time footage like this can help scientists figure out. And it’s also an important reminder that while we humans love to assume that nature has a ‘plan’ or a system, in reality, it’s often a whole lot messier.
Life, at a molecular level, has mastered parallel processing. It also guesses, tries things and then adjusts based on feedback. We assume that there is some kind of feedback to coordinate DNA replication, but it may be something surprising, like quantum effects. Stay tuned for surprises.