Author : Pascal Wery

E-mail : pascal.wery@gmx.fr

https ://www.pascalwery.com

Orcid : 0000-0002-5028-7869

From : Catholic University of Louvain, Walloon Brabant, Belgium

Références: American Journal of Planetary and Space Science (AJPSS), 05 June 2025
DOI: https://doi.org/10.36266/AJPSS/142

The topic:

Finding the origin of the eukaryote cell.

Abstract:

The origins of the eukaryote cell, which is very complex compared to bacterias,  remain a mystery. Still, straight DNA allows a better capacity for adaptation and therefore for evolution than a circular one. So it is the structure of the DNA that must have changed first.

Introduction:

We start with the observation : what distinguishes eukaryotes from protists are mitochondrias. Eukaryotes do have them while protists don’t. Then, we compare prokaryotes and protists : the procaryotes have a circular DNA arrangement while the protists' arrangement is straight. As a result of these differences, we can guess how they have appeared.

The result :

The evolution opened the circular DNA of a procaryote which became the first nucleus cell.

Finally, this cell eventually acquired mitochondria by symbiosis with aerobic bacterias.

Literature Review:

Biologists have understood the value of mitochondria. These organelles inside our cells produce ATP, in other words : energy. The energy efficiency that they give while treating oxygen is very ergonomic. They also have understood that it comes from a symbiosis with an aerobic bacteria. But for a long time they neglected the protists.

Protists are nucleated cells, but they have no mitochondria. Nevertheless, the protists were considered as eukaryotes, in other words, nucleus cells with mitochondrias. But these are just nucleus cells. So what happened ? Protists would have got ridden of their mitochondrias ? Getting rid of a very ergonomic system is not logical. What is logical is to acquire it and not to get rid of it. Thus, the protists are nucleated cells that have not acquired mitochondrias. These are nucleated cells having no symbiosis with aerobic bacterias. In short, they are a primitive species. They arrived before eukaryotes. The eukaryote cell is just one of their evolution. An evolution that had said : « I need to treat oxygen ! »

But how could this evolution have appeared ? Because of the environment. An environment that changes. A deglaciation ! Probably one of the cryogenian’s deglaciations. A deglaciation is much faster than its opposite. Therefore, a deglaciation introduce a global and brutal climate change. A deglaciation also provides not only ozone in the atmosphere, but oxygenated water in the oceans and seas too. However, oxygen is disruptive, especially when it is unstable, as it is with hydrogen peroxide.

« It is not the strongest of the species that survives, nor the most intelligent. It is the one that is the most adaptable to change. »

Charles Darwin

Findings:

Thus, here is the nucleus cell struggling with oxygen. It's the struggle for survival. In these waters, the protist must evolve or disappear. Therefore, many are those that disappear. But somes struggle. They fight against oxygen to survive and the only effective way is to use the aerobic bacterias to neutralize it. Those who do it survive and evolve. As a consequence, they form a symbiotic relationship with bacteria, which eventually turn into mitochondria. In short, it is the necessity that brought the mitochondrial symbiosis. It appeared after the nucleus cells. But it's not what has created nucleated cells. These already existed for a long time. They existed since the protists.

Discussion:

So here are the protists : they are nucleated cells but they have no mitochondria because they haven’t symbiosed with aerobic bacterias. The eukaryotes did it, but not the protists. Eukaryotes are therefore an evolution of ancient protists. Protists which eventually symbiose following changes in the environment.

But how did the first nucleus cells arrive ? We must get back into the context : in this ancient time, there were only viruses, bacterias and archaeas. So at that time, apart from the viruses, there was only DNA in a loop. However, the nucleus cells are open and straight strands. Strands that had been closed with an envelope. This is where the nucleus cell was born.

Thus, the reign of the living has improved from the closed and circular DNA of prokaryotes to the open and straight DNA of protists ! How could such a change occur ? Answer : with the change of the environment… as always ! But what environment can cause such a change ? Answer : another deglaciation. This time, it was the Huronian’s deglaciation.

Indeed, hydrogen peroxide is a disruptor. By pouring into the water after the thaw, it affects the living, in other words not only bacterias or archaeas... but also viruses ! Thus, during a deglaciation, the number of disturbed viral attacks increases sharply. Therefore, the increase in the rate of mutations makes probable what is unlikely, in other words, the mutation that changes everything ! Spontaneous mutations are rare, random, and hazardous unless a mutagen disturbs the environment. Therefore, they become inevitable. This does not mean that there will be evolutions but disturbances unless this disturbance is widespread and constant. In this case, the probability of an advantageous spontaneous mutation increases with the rate of mutations until it becomes unavoidable. This is the famous : « it only could happen ».

Mutagens are usually chemical compounds, radiation or viruses. The first two causes give disorganized random consequences since the DNA is altered anywhere while a viral attack is more targeted. Now, by combining two phenomena, environmental change and viral attack, we obtain a much higher probability of advantageous mutations. In this case, prokaryotes are more attacked by « damaged » viruses, in other words : viruses whose targeted attack on genetic material can only fail ! So sooner or later there will be a genetic benefit. An advantage that will allow the cell to improve. The whole point is to understand this improvement thanks to the consequences it generated : the appearance of the nucleus cell, in other words, a cell capable of compartmentalizing itself, thus creating a fibrous network, thus creating a new protein, thus creating a new ribosome whose code is in the DNA ! A DNA that has changed as a result of a mutation. A spontaneous mutation.

Indeed, a viral attack has opened the DNA code of an archaea. However, it did not kill the archaea since the attack was disrupted by oxygen. But that affected the archaea and it could not close its code because « something » was introduced into it. Thus, it remained definitely open. But the archaea, although ill, nevertheless survived. It did adapt because this « something » has given a selective advantage that allowed the archaea to adapt to oxygen. An advantage that also gave the ability to weave a fibrous network inside the cell and cure the archaea from its illness by closing its code with an envelope.  Thus, the medicine must have come with the disease. This is what allowed the archaea to survive and to compartmentalize its own body. Thus, it will evolve and the cell will become more complex. Thus membranes appear that divide the cell. One of them is the nucleus. It surrounds the DNA in order to close the strands, although DNA remains open. This new disposition brings greater adaptability since open/straight DNA adapts more easily to changes while a circular DNA is deaf and blind : it doesn’t change so easily.

In general, prokaryotes have only one circular DNA molecule and therefore only one replication origin (the two-stranded DNA replication unit). Eukaryotes have several replication origins on each chromosome. This makes several « ori » (promoter sites) per replicate (smallest replicable DNA unit)… on each chromosome ! That makes many « ori ». Thus, the prokaryote usually presents only one replication site that can modify its DNA. Consequently, its chances of development are low. So it evolves very slowly. The nucleus cell, on the other hand, with its many « inputs » (ori), allows more possibility of mutations. Thus, its chances of evolution are greater. However, this also requires mechanisms of controls in order to maintain a viable DNA. Thus, an open (straight) DNA is more likely to evolve than a circular one.

Conclusion:

Thus appears a new form of life, the protist. That is the first nucleus cell. And since it adapts more easily, the evolution will make a leap forward. Thus, new RNA compounds appear which allow a better management of the information. RNA Messenger among others which is becoming more and more complex. Thus, the new cell becomes increasingly autonomous and it is growing ever to contain all new compartments.

Conflict of interest:

This theory is related to a French book : “Les origines de la vie”. This book belongs to a catalogue named “Les Enseignements de l’Ange”. This collection got a lot of theories. So, there is a conflict of interest: being right makes sales while being wrong makes idiots! This can lead to human blunders. This is why we must exercise caution: because conflict is unavoidable, these observations can only be validated if they are confirmed by peers.

The debate:

Science is strange: We make extraordinary discoveries but since we do not understand them, we often miss out on little wonders. Here is an example: perturbations lead to adaptations. The great oxygenation event was the one that pushed microbes the most towards evolution. And in this event, the highlights were deglaciations. Two periods where consequent: the huronian and the cryogenian. Both of them gave global deglaciations and each one is linked to a microbian evolution : the appearance of protest for the first and eukaryotes for the second.

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