How did RNA and complex enzymes emerge for DNA/RNA replication?

[TubbaBlubba]

I recently saw some rather neat real-time replications of DNA being replicated in my Chemistry class (Still in High School). The intersting thing is that this requires some astoundingly complex enzymes to work. I would take a wild guess and say that an RNA-based organism would have a significantly simpler replication system, but what I cannot quite wrap my head around is how RNA and these, well, nanomachines of enzymes would end up emerging at the same time; as my chemistry teacher said, "It's almost enough to make you religious".

The only thing I could imagine would be a replicating enzyme actually building the strings in the first place from loose phosphates, ribose and nitrogen bases.

Any thought or insight into this? Actually, any further information on this in general would be of interest to me.

 

[phyzguy]

Try reading this:

http://en.wikipedia.org/wiki/RNA_world_hypothesis

 

[TubbaBlubba]

Ah, very interesting. Thanks a lot.

 

[bobze]

I recently saw some rather neat real-time replications of DNA being replicated in my Chemistry class (Still in High School). The intersting thing is that this requires some astoundingly complex enzymes to work. I would take a wild guess and say that an RNA-based organism would have a significantly simpler replication system, but what I cannot quite wrap my head around is how RNA and these, well, nanomachines of enzymes would end up emerging at the same time; as my chemistry teacher said, "It's almost enough to make you religious".

The only thing I could imagine would be a replicating enzyme actually building the strings in the first place from loose phosphates, ribose and nitrogen bases.

Any thought or insight into this? Actually, any further information on this in general would be of interest to me.

The problem with that line of thinking is, it only reflects on modern cellular machinery-some 3.5+ billion years in the making.

A replication system doesn't have to be perfect (nor even sensible), it only has to allow one thing to happen-Evolution by natural selection. Once a system arises capable of that then were off the races.

Replication could be something as simple as polymerizing polynucleosides (which do so in the presence of UV light), 'competing' for available nuleosides.

 

[LudusRex]

Thank you for sharing your experience with DNA/RNA replication in your chemistry class. It is truly fascinating to witness the complex processes involved in replicating genetic material. As you mentioned, the enzymes responsible for DNA replication are indeed highly specialized and essential for accurate and efficient replication.

Your speculation about RNA-based organisms having a simpler replication system is actually quite accurate. RNA viruses, such as the flu virus, do have a simpler replication process compared to DNA-based organisms. This is because RNA is a single-stranded molecule and does not require the same level of proofreading and error correction as double-stranded DNA.

In terms of the emergence of RNA and enzymes for replication, it is believed that RNA was the first genetic material to evolve in early life forms. This is because RNA has the ability to both store genetic information and act as an enzyme, performing chemical reactions necessary for replication. This is known as the RNA world hypothesis and is supported by evidence from studies on ancient RNA-like molecules.

As for how these enzymes may have emerged, there are several theories including the "RNA-first" hypothesis, which suggests that RNA molecules could have formed spontaneously from simple building blocks in the primordial soup of early Earth. Over time, these RNA molecules may have evolved the ability to catalyze their own replication, eventually leading to the development of more complex enzymes.

I hope this provides some insight into the fascinating world of DNA/RNA replication. If you are interested in learning more, I would recommend exploring the RNA world hypothesis and other theories on the origins of life. Thank you for your curiosity and keep asking questions! That is what science is all about.