It seems the only place investigators “find” circular eukaryotic DNAs these days is when they’re looking at cancer cells, micronuclei, and chromosomal rearrangements. They call this DNA “pulverization” (see article link below). The chromosomes are literally “going nuts” with each cell division, breaking up and rearranging whatever is left. DNA replication becomes asynchronous, meaning a sizable number of these DNA chunks take on a life of their own, as if they were microorganisms in their own right. My question is simply this: How the hell does this happen? By magic? Nobody seems to know. But I think I have an explanation for it. Check out the rest of my blog.
I googled circular DNA today in a variety of formats and all I could come up with is journal articles dating back to the early 2000’s or earlier. If anyone knows of more recent articles relating to this topic I would appreciate an update. Otherwise, I must assume the scientific community has moved on to better (or easier) things.
The one shown below is a 2002 article.
The facts still stand: How do you generate thousands of circles with orders of magnitude size differences from 40 linear mouse chromosomes? The most obvious answer is that they were already present in a cryptic form (click photos to enlarge).
Degrading mouse cells, 400x magnification
What do mouse chromosomes look like under “normal” conditions? Check out this link: mouse chromosome.
How do you create a simple linear stretch of DNA that goes on and on, like some kind of endlessly meandering oil pipeline?
Well, first of all, you beat the living hell out of it so it breaks up into fragments. Next, get rid of any nonlinear fragments because, face it, they can’t be sequenced anyway. This is most easily done by throwing out the phenol phase used for DNA extraction which may contain any troublesome DNA/protein/lipid etc interactions. Next, take what’s left (linear DNA fragments) and artificially splice them together in your mind using overlapping sequences. If this doesn’t always work, just extrapolate until it does. Voilà! We now have a nice, neat (if somewhat boring) endlessly linear, stretch of DNA.
I find it amazing that scientists are able to tinker with DNA to generate an apparent infinite variety of two and three dimensional objects that are incredibly complex, detailed, and highly symmetrical, some like snowflakes. You can learn more about this nanotechnology by clicking on the link below:
So my question is this: Why is it so difficult to connect the dots here? If man can generate such a wide array of DNA superstructures, why can’t nature? More to the point, the ability to exploit DNA in such a fashion is more than mere coincidence. Nature has been using complex DNA superstructures for eons to generate the chromosomes necessary for the complexity of multicellular life that now exists on this planet.
Hypothetical natural DNA “origami” (circa 1991)
Learn more about natural DNA “origami” by reviewing this blog or contacting Dr. Frank Abernathy: firstname.lastname@example.org
This link is very interesting and at first glance seems totally unrelated to what usually appears on my blog. However, though the discovery is quite fascinating and worth reviewing, I mention it here for a different reason: The initial reaction of the scientific community to what they regard as heresy.
Horizontal gene transfer in this blog suggests that our very chromosomes were constructed by it. Is this a process that happened eons ago and is now relegated to the dustbin of history, occurring only within primitive life forms like bacteria?