Follow the palindromes to see how life evolved.

You may have heard the catch phrase “follow the money” in the film, All the President’s Men.  Following the money led to an understanding of just how everything works in a money-driven social environment.

The same thing may be said about palindromes in terms of biological evolution. A palindrome occurs in DNA or RNA and results in a form of molecular mirror image symmetry. When such DNA is melted and allowed to cool quickly, it snaps back on itself, forming characteristic hairpins of DNA or RNA.

Palindromes in DNA are generally associated with regions that are involved with DNA replication, gene expression, and cellular differentiation. In other words, they seem to be involved in starting points that make DNA “tick”.

In my last post, I discussed origins of replication as not only agents of replication and localized gene amplification, but also precursors to other elements such as promoters of transcription, enhancers of transcription, and splice sites for changing the very coding of the DNA itself. In all of these structures, palindromes seem to be lurking nearby in some form or another. I have designed some models to explain how origins of replication are formed, amplified, and converted into other structures like promoters, enhancers, and splice sites. However, be warned: This is not your typical linear DNA strand model so prevalent in textbooks and scientific literature. This model is based upon hierarchical DNA circular structures which are, themselves, composed of even smaller circles that may themselves be composed of still smaller circles and so on. You will need to dive into the blog further to get a better grasp of what this all means. However, I will place one set of models here again to get you on your way.

Fig 17Fig 18fig. 23fig. 24

Fig. 1 (top left) undifferentiated DNA replicon cluster

Fig. 2 (top right) differentiated DNA replicon cluster

Fig. 3 (bottom left) RNA transcriptional pathway along the DNA

Fig. 4 (bottom right) splicing out of introns from pre-messenger RNA to generate messenger RNA

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About frankabernathy

I am a retired cell biologist and alumnus of Ohio State University. I became interested in chromosomes as far back as the 1960's when I wrote a term paper on the effects of radiomimetic drugs on chromosomes. I was fascinated at how they could break apart and reform new structures so easily. I became further involved in the early 1970's after taking a cytogenetics course at the University of Arkansas. I took that knowledge with me to Ohio State in 1980 where I eventually worked on my research and completed my Ph.D. dissertation, "Studies on Eukaryotic DNA Superstructure". My studies and later research suggested that the DNA within the eukaryotic chromosome is not the simple, linear molecular thread so widely suggested in all the classic textbooks published today. Instead, it may be the culmination of a geologically rapid set of endosymbiotic events where microorganisms plug into each other to create something greater than themselves. Feel free to contact me at fabernathy@sbcglobal.net.
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