Researchers from the University of Oxford in the United Kingdom compared the oxygen sensors in humans and in a primitive amoeba-like creature, and discovered that it is exactly the same mechanism
Researchers at the University of Oxford, funded by the British Biological Research and Biotechnology Council, have discovered a clue that may help explain why the first evidence of multicellular animals appeared 550 million years ago and not earlier, when atmospheric oxygen levels rose sharply from 3% to 21%.
The team led by Prof. Chris Schofield discovered that humans share the oxygen sensing system with the simplest known animal Trichoplax adhaerens, suggesting that the system has existed since the first animals appeared 550 million years ago.
The discovery, which will be published in the January 2011 issue of the journal EMBO Reports, sheds light on the question of how humans sense oxygen and how oxygen levels drove the first stages of animal evolution.
According to Prof. Schofield, "it is essential for any multicellular creature to have a regular supply of oxygen to almost every cell, so the increase in oxygen levels in the atmosphere made the existence of multicellular animals possible.
"There still remain various physiological challenges for organisms to move from the ancient configuration of single-celled organisms such as bacteria. Being multicellular means that the oxygen has to reach not only the cells on the surface of the creature. We believe that this is what motivated the ancestors of Trichoplax adhaerens to develop systems to sense the lack of oxygen in each cell and do something about it."
The oxygen sensing process allows the animals to survive better in low oxygen levels, or hypoxia. In humans, these systems respond to hypoxia, such as that caused by high altitude or physical exertion, and are essential for preventing strokes and heart attacks as well as some types of cancer.
Trichoplax adhaerens is a tiny seawater creature that lacks any organs and has only five types of cells, giving it the appearance of a structure. Analyzing the way Trichoplax adhaerens reacts to the lack of oxygen allowed Oxford researcher Dr. Christoph Lorenz to discover that it uses the same mechanism as humans. In fact, when an important enzyme from the Trichoplax adhaerens is transferred into human cells it works just as well as the corresponding human enzyme.
They also examined the genomes of several other organisms and found that this mechanism was inherited in multicellular animals, but not in the single-celled organisms that preceded the animals, showing that the mechanism evolved at the same time as the first multicellular animals.
Defects in most oxygen-sensing enzymes in humans can cause polycythemia - an increase in the number of red blood cells. The current study also opens the door to new approaches to developing treatments for this disease.
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The answer to all this, as to many other things, is evolution. ... Practically: if there was a lot of carbon dioxide on Earth, then it took a certain amount of time for production to develop that was really suitable for them (everyone else that didn't develop - died and that's why they didn't enter the Bible. Everyone else greedily consumed the available product and threw out what was unnecessary After that, they were tempted by productions that took the needs of the first ones and used them as a precious thing for life and made their own needs that- ….
Alon (11):
The question was, and I quote: "I wonder what caused such a huge jump in oxygen levels."
Sit with yourself and think about why you attempted Lucci's question and added the word "sudden" to it in your response.
Lucci may have wondered about the high rate of increase in oxygen concentration as you suggest and may have wondered about the cause of the increase in oxygen concentration in the first place. This cannot be known from his response as written unless you read minds (or if you and he are the same person or if he told you this on another communication channel, etc.). Even if Lucci informs us now about his original intention, this will not change the fact that you rejected my answer and that without any justifiable reason. If you thought Lucci meant to ask something else you should have verified it with him or offered him an explanation parallel to mine. It is not clear to me why you presented in your original response as if I missed the main point and perhaps you should also think about the reason for this act of yours. Maybe it has to do with the fact that you wished for a sad New Year's Eve.
For the last Camila (8) - the question was what caused the sudden huge jump in oxygen levels and not the cause of the oxygen generation, and the answer is the saturation of the oxygen absorption. Without the minerals and iron there would have been a permanent and gradual increase in the oxygen level, the end of adsorption created a catastrophic boom...
Wishing you a pleasant and sad New Year's Eve
Is the rapid increase in the percentage of oxygen in the atmosphere due to the development of chlorophyll during this period?
Tiktallik (7):
Um... thanks.
In my environment there are other women and they are much smarter than me and I assume that in many other places there are also other women whose abilities are no less than mine, therefore I am forced to come to the conclusion that you do not hang around in the right places or manage to miss those women even when they are right in front of your nose (perhaps because the mirror Theirs is not cool enough? :-))
Alon (5):
I disagree with you. Without photosynthesis, free oxygen would not have been created in these quantities in the first place. The trapping of the oxygen in the first stages only delayed the process but the delay in itself, as interesting as it is, is not the main thing (see what the title of the article says). Do you agree that without photosynthesis the oxygen catastrophe would not have occurred but without the minerals and iron it would have occurred anyway? Lucci (1) asked what was the cause, not why there was a delay...
withering
will you marry me You are the smartest and brightest woman I have ever come across!
Your genius comments made me fall in love with you!
Thanks everyone for the answers 🙂
To the last Camila: Regarding photosynthesis, that's not the main point here. It existed both before and after the oxygen catastrophe event. The point is that the various minerals, mainly iron, were already saturated with oxygen and then massive amounts of free oxygen began to be released into the atmosphere due to the activity of photosynthesis and the products of anaerobic life and this began to create the catastrophe.
A genius conclusion.
Maybe the amoeba was also green and did photosynthesis.
Lucci (1)
In one word: photosynthesis. In two words: photosynthesis.
http://en.wikipedia.org/wiki/Great_Oxygenation_Event
Lucci,
According to the accepted theory today, life began in anaerobic cells (which do not use oxygen) and the oxygen is emitted from them as a toxic by-product for them (since it causes the production of free radicals). Over time, its concentration in the atmosphere rose to levels that almost made their life impossible and they were pushed into low-oxygen niches. It can be looked at as the first massive air pollution.
But then there was an amazing turn and a cell was created that was not only resistant to the toxic oxygen but actually used it with enormous efficiency to produce energy and raised the utilization from 2 ATP molecules (the cellular energy currency) created from one glucose molecule to 38! And so the way was paved for multicellular organisms and the variety of oxygen-based life as we know it today.
The remains of those primary cells can be seen in the soil, swamps and other low-oxygen places.
I wonder what caused such a huge jump in oxygen levels.