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A fresh look at the wrinkles of old age

Important genes, and not damage to the cell and DNA, are the causes of aging

By Melinda Wenner

Old age torments all creatures on earth, and everyone dreams of a cure. But even after decades of research, aging remains largely a mystery. Now, new findings suggest there's a good reason for the dead end in research: Scientists may have simply been investigating the wrong causes. New evidence shows that aging is not the result of the accumulation of genetic and cellular damage, but the result of the disruption of genetic programs that control developmental processes.

For 50 years, this field of research was dominated by the theory that aging is caused by stress states and active forms of oxygen: "free radicals" that are naturally formed as byproducts of the body's metabolism. Studies conducted on the worm Caenorhabditis elegans showed that reducing exposure to reactive oxygen species extended its life span, and worm strains that lived longer were also more resistant to stressful situations. But only a few studies have conclusively linked damage caused by oxidation to changes in cell activity.

Scientists have even noticed internal genetic changes that accompany the aging process. In aging mice, the gene p16INK4a, which controls cell regeneration and growth, becomes more active in most tissues. The gene prevents normal cell regeneration in response to injury or disease as happens in younger cells. Also, in stem cells in the muscles of old mice, unlike those of young mice, protein complexes accumulate that change the muscle, over time, and make it into fibrous and fatty tissue.

However, the findings failed to challenge the notion that aging is the result of cumulative damage, because these genetic changes may be the result of aging rather than its cause. "That's always the challenge, to try and distinguish between cause and effect," says Brian Kennedy, a biochemist at the University of Washington. Although studies have shown that changing the expression level of certain genes can affect the lifespan of living beings, it is not clear whether these genes are also involved in the natural aging process.

However, an article published in the scientific journal Cell claims that genetic programs do cause aging. Scientists at Stanford University and the University of Colorado at Boulder compared the genes activated in young worms and the genes activated in old worms. They found more than 1,000 genes that showed changes in expression level, but most of them were under the control of only three genes: ELT-3, ELT-5 and ELT-6. These genes are transcription factors, i.e. molecular switches that turn other genes on and off. "There were hundreds of factors that went wrong, but they all led to these three transcription factors," which are involved in the differentiation of specialized cells found in different membranes in the body, explains Stuart Kim, a developmental biologist at Stanford University and one of the authors of the paper. Differences were also found in the level of expression of these three transcription factors themselves in a comparison between young worms and old worms.

To see if cumulative damage ultimately affects these transcription factors, the scientists exposed the worms to oxidative stress, pollution, and radiation, but none of these affected gene expression. The changes appear to be "internal changes in the worm's genome," says Kim, and are not influenced from the outside. Moreover, when the researchers stopped the expression of the ELT-5 and ELT-6 genes, whose activity is usually increased in old age, the life expectancy of the worms increased by 50%. "I was totally surprised," says Kim.

The findings of the study are also consistent with the popular opinion linking life expectancy and calorie consumption. The researchers discovered that the three transcription factors are controlled by an insulin-like signaling pathway, which controls the metabolic changes of the organism in response to starvation. One of the actions of the insulin-like pathway in a state of limited calorie intake, says Kim, is to "reboot" the transcription factors from the ELT family, or the corresponding genes in other organisms, and return them "to a younger state." Scientists believe that the plant compound resveratrol, which extends the life span of certain creators, mimics the effect of restricted calorie intake and even reboots these signaling pathways.

Kim does not believe that the transcription factors are pre-programmed to cause aging. He hypothesizes, instead, that their activity simply gets out of balance as the worms age. After all, evolution selects genes that help an individual to reproduce, but once the organism has passed reproductive age, it is no longer subject to the effects of natural selection. "Entire biological systems drift and go out of balance when nature no longer cares about them," says Kim. The ELT-3, ELT-5, and ELT-6 genes may play an important role in the development of young worms, but once they have finished their role, their activity can go awry, and this "developmental drift," as Kim calls it, can cause aging.

The study does not prove that aging in worms is caused solely by developmental drift, Kennedy notes. Both cumulative damage and developmental drift may play a role, and additional genetic pathways may be involved. But the article certainly provides scientists with "food for thought as to the causes of the aging process," he says. "The Marmak brings to the fore a new hypothesis that can be examined in more detail."

What do these findings mean for humans? If aging is primarily a genetic process, it may one day be possible to prevent it. No one knows if the genes corresponding to the ELT family in humans, called GATA family transcription factors, are also involved in aging, and Kim and his colleagues hope to address this issue soon. "We know how human development happens," says Kim. "Now we have to find out which pathways are not functioning properly in old humans."

Melinda Wenner is a reporter from New York City.
The article was published in the December 2008 - January 2009 issue of the journal Scientific American-Israel

for her photo and license

41 תגובות

  1. Since I have no training and/or biological knowledge whatsoever, I wanted to ask a somewhat rhetorical question that might be able to direct this discussion a little in a different direction:
    Why not see a person as an integral part of a larger machine, such as termites which function as a unified organism? And the point of this is to try to deal with the aging mechanism.

    The evidence that a person is an integral part of the cycle of life is categorical, such as a woman's menstrual cycle and the like. Therefore let's assume for a moment that man is indeed an integral part of a larger system, and if we take this logic and subject it to the issue discussed today, then it can be assumed (albeit a priori) that the large organism of which man is an integral part externally dictates the encounter of the human body, or in other words the mechanism of death is not inherent in us but is dictated to us by a factor of which we are an integral part (the prototype).

    The question arises as to what is the huge organism that we are a part of (with termites it is easy, it is simply the colony, which functions as a war machine when attacked), does the same parallel exist with us as well? And if so, then maybe at the experimental level you could just claim that in a state of stagnation, complete stagnation of the "collective organism" of the person / environmental conditions, maybe the death mechanism would stop working.

    Therefore, perhaps the solution is to first find what is the true "collective organism / prototype" of the person "as a screw", and treat the problem externally to the body? Apparently the answer is an image of some kind of energy at the bang level that can explain this (or I see too many STARTREK)..

  2. fresh:
    Read everything I said.
    I explained why an infertile parent's competition for resources harms the survival of the offspring (his own) and therefore the distribution of genes (his own!).
    It goes without saying that evolution will not promote a trait that impairs survival.
    Now let's see your offer.
    Are you saying that they will find out (evolutionarily) creatures that bring fewer offspring?
    This is exactly equivalent to the offspring dying after being born.
    This decreases gene distribution rather than increasing it.
    The demographic problem in Israel shows exactly what happens when there are individuals who bring more offspring than others.
    It is clear that evolution also places a limit on the number of offspring, but the reason for this is not the need to "maintain" the parents after the reproductive age, but the need to allow the parents to take care of their offspring and maximize the number of survivors among them.
    That is why parents who invest in examining their offspring produce fewer offspring and parents who ignore their offspring from the moment they are born produce much more offspring.
    By the way - "investing" parents also live a little longer after reproductive age because they can continue to take care of education and other assistance in a way that will increase the survival of their offspring.
    It's all a matter of fine tuning - to what point does your life contribute to the survival of your genes and from what point do they start to be an obstacle.
    It seems to me that you are fundamentally confused by attributing to evolution any motivation to keep someone alive.
    Evolution is simply a law of nature whose cause is the laws of statistics. She has no motivation and in particular no reason for her to "take care" of the survival of an infertile parent.

  3. And how exactly did you conclude that nature does not accept her? The fact that in nature parents die does not mean that the reason for this is to prevent competition for resources between parents and offspring

  4. fresh:
    What you say makes more sense makes no sense at all.
    I don't know what you base your opinion on but it turns out that nature doesn't accept it.

  5. Michael:
    In my opinion, it makes more sense for nature to control the dosage level of the competition between parent and offspring for resources, by reducing the average number of offspring that the parent can produce and not by killing the parent.

  6. fresh:
    In general, I agree with you, but if you read my responses in this discussion, you will see that I left room open for the exact reasons for the malfunctioning of the various mechanisms, because not only free radicals can destroy.
    Therefore aging is, in my opinion, simply the result of cell destruction and the imperfection of their repair mechanism.
    Still - what is written in the article is true in the sense that mutations that improve, for example, the ability of the heart to function for a long time will not give their owners an evolutionary advantage when the addition is after reproductive age. On the contrary - such mutations may be a disadvantage in that they cause the parent to compete with its offspring for resources and thus reduce the number of their offspring (which are indirectly its offspring) without increasing the number of its direct offspring.
    It is therefore reasonable to expect that tissue preservation mechanisms will not evolve to give a creature life well beyond reproductive age.
    So why is reproductive age limited?
    Because nature has not yet succeeded in creating repair mechanisms that would preserve the ability to reproduce indefinitely.
    It should also be remembered that evolution follows its thumb and cannot recognize the potential advantage of a reproductive mechanism that is able to survive longer than the weakest vital link (because it doesn't matter how powerful the mouse is - in no case will it be able to reproduce after it dies).
    It is somewhat similar (but not the same) to what is called Deadlock in computers - no mechanism that is not the weakest link of the organism will improve before the weak link improves.

  7. Ra'anan, you are 'right' again :) especially if you understood the essence of what you wrote in quotation marks.
    Over the age of 40 (the age of understanding) if a natural birth occurs (from a covenant - a sacred partnership) then it arises from the G/J factor of the 'heart' memory, the true conscious and innocent 'higher desire' of the noble and higher rest of the 'spirit' ( Indeed, a magical and sublime wonder. Even if conscious and 'temporarily forgotten', a pinch of wonder remains in it and nothing is taken for granted!).
    And if you have already talked about 'free radicals', take the meaning of the words to other places, in order to understand more.
    Well, and if there is no agreement, apparently there are always the wonderful and incomprehensible "outliers" by the Ohazin in the selective "free will". The vision of the "derivative" supreme purpose is lacking:)

  8. "Evolution selects genes that help an individual reproduce, but once the organism has passed reproductive age, it is no longer subject to the effects of natural selection"

    But why did nature even create a reproductive age? If it were possible to live forever, nature would not create aging and mortality that would limit life span just like that for no reason. After the reproductive age we are indeed not subject to the effects of the natural barrier, but why is the reproductive age actually up to the age of 40? Why not until the age of 100 or 1,000 or more. Therefore, in my opinion, nature did not create special genes whose role is to limit the life span of the organism. In my opinion, the reason for aging must be that the free radicals cause damage to the transcription that over time cause the destruction of the organism and, long before that, cause greater chances of birth defects in the offspring of the organism.

  9. Stop trying to look for all kinds of magical explanations for aging,

    There is an excellent explanation that is based on many findings, the body is really trying to protect itself but there are other causes of death such as lack of food or predators, which causes some types of "beef" to prefer to reproduce quickly and "format" the results of their genes each time instead of developing complicated defense systems with a high metabolic survival cost, while other types of animals that survive better over time accumulate useful mutations in this area and this is observed even on the same species on different islands and under different conditions on each island. On the other hand, mutations that cause aging after a certain age that no one has reached even within civilizations of Humans just stayed.

    Why does a person have a maximum life expectancy more than 2 times higher than a chimpanzee (with the same living conditions)? , because humans possess a higher survival capacity that monkeys do not have, therefore it is noticeable when you die at the age of 20 and nature allows you to genetically live for about 40 years instead.

    Of course there is damage to the genes, but it's obscurity, it's a free space for a doctoral student to say that there are genes in a person that cause him to self-destruct because it's some kind of advantage we inherited from our ancestors...

    My opinion from what I have read so far is this, and that there are hundreds of factors of aging, one of which is the first in line to kill us in the case of one or another lifestyle, advances in medicine can eliminate it and then comes the next one. In a short time, humans will more than triple the life expectancy (which is already high for mammals of this size) in a few years they will invent something else and for those who live in a sufficiently developed society, the life expectancy will increase (if he does not lead one or another lifestyle that will kill him, let's say from obesity diabetes II or a high chance of AIDS)
    In a little while, we will eventually reach a stage where we have processing minds and knowledge in such an amount that for every year that we need our life expectancy will increase by two years and it will be a sort of long transitional stage in society.

  10. According to a well-known theory, the death of somatic cells is caused by the shortening of the telomeres, the structure at the ends of the chromosomes, and not as a result of an inability to maintain the cell.
    You can

  11. Indeed, there is no limit to the level of simplification that can be reached at the philosophical level. What I did try to clarify is that as the level of complexity increases, the capacity for renewal decreases. What is relevant from the example of the hydra, is that if you want to be immortal, you probably have to give up the level of complexity you have reached. And it is a fact that both the hydras and their friends are with us and so are we, so both choices have been determined by natural selection so far.

  12. light:
    Theoretically it could be that the "root" of the bud is after all a special cell where the clock is reset like in the sex cells, so your words are not real proof.
    What's more - you shouldn't argue with facts and the experimental findings show that "the hydra ages very slowly if at all" If I'm translating, look for what I found on Wikipedia:

    It turns out, then, that the hydra is probably immortal, but it is, as mentioned, a very simple creature.

    By the way, on a philosophical level, animals can be seen as simply a stage in the life cycle of the sex cells.
    If you think about it this way, then the immortal gametes "put on" at one point in their endless life cycle the body of an animal and shed it at another point.

  13. Ariel:
    As Michael clarified, I was indeed talking about the ability to regenerate and compared it between different organisms, according to their level of complexity. I argued that as the organism becomes more complex, it loses its ability to regenerate. Also, I explained what asexual reproduction is through autotomy.
    We will now look at the hydra, an organism that reproduces in two ways: sexually (sperm cells and egg cells, different specifications) and asexually. In the discussion I will open I will look at asexual reproduction.

    Hydra has a reliable reproduction mechanism called "budding". This means, the "parent" develops a small hydra, genetically identical to him, on his own body. When the bud is ripe, it detaches from the parent and functions as a hydra for everything, with the same genetic load as the parent (think of them as clones or identical twins born at different times).
    Suppose a ticking clock does exist in Hydra. According to this assumption, the clock is ticking in all the cells of the body except the sex cells, because otherwise the species would be extinct (Michael developed this discussion in a previous message). Thus, in each and every cell of the hydra that is not a sex cell, there is a ticking clock that tells it, approximately, when to die. From this I conclude that the clock is also ticking in the bud, the future offspring, of the hydra, when it is still attached to the parent. When the hydra sprouts a bud, it and the bud are the same creature, meaning they age at the same time and the ticking clock in them shows the same time (they have the same number of divisions to live, or the same time to live, as you wish). When the bud detaches, there are now two different creatures (a problematic definition in itself, what is one creature and what are two different creatures), and in both of them the ticking clock indicates the same time of death. That is, the parent and the offspring age at the same rate - when the parent is old, the offspring will be just as old as him! To illustrate, it is worth in your soul that you will show signs of old age like your parents, even though they are older than you.
    Protect the contradiction. If the bud and the parent die from the ticking of the clock (old age and death are predetermined) at the same time, then asexual reproduction has no benefit - it does not create a new and young generation, it creates a new and old generation just like its parents. It is a fact that the hydras continue to reproduce in this way (this is how we opened our discussion), contradicting the conclusion we reached based on the assumption that they have a ticking clock.

    Because of this, I disproved the existence of a ticking clock in a complex multicellular creature. Is it possible to deduce from this even more complex creatures? little I will leave the implications to qualified biologists…

  14. Ariel:
    Or spoke about the ability to regenerate organs and not about eternal life.
    The ability to conceive is also usually limited and the replacement organ is less developed than its predecessor.
    I don't know of a single complex animal that doesn't age.
    It is possible that very poor creatures like the hydra do this but no truly complex creature is capable of living forever.
    There is no doubt that eternal life would increase the inertia of evolution, but this increase in inertia could be compensated for by a greater mutation rate.
    There is a complex mechanism here that is difficult to know (and therefore no one knows) all its parameters and the only way to check if it really works is by observing nature.
    To claim that death was determined by evolution, one must point to species of complex animals that became extinct only because they were immortal.
    I don't think any evidence of this kind has been found.
    Do you know anything else?
    The fact that nature did not solve all the problems does not indicate that there was no need to solve them, but only that it did not find a solution for them.
    Isn't there an evolutionary advantage in being able to overcome the animals that prey on you?
    Certainly there are, but there are still animals that have not been able to develop such resistance.
    In particular, the human race has not been able to develop resistance against various and unusual diseases, even though in the laboratory it manages to create drugs against them.

  15. And I will add: and the old body competes for resources with the new bodies created from it. And when the old body dies after a few genetic clock ticks - intrasexual competition is reduced.

  16. Or and Michael: Your claim that it is difficult to maintain and renew cells that have differentiated in multicellular organisms (as I imagine about 260 types of cells in humans), on the other hand, Or gave several examples of invertebrates that can regenerate and live forever (although they have fewer types of cells, but they still have differentiation of cells).
    You claim that during evolution multicellular creatures lost or failed to develop ways to overcome death and old age, but we have several examples of dealing with death and old age!

    What's more, in the laboratory, as the experiment above proves, it is possible to control the lifespan of creatures! Why can't the laboratory tricks performed by the researchers in complex multicellular organisms develop by themselves due to genetic changes?

    Perhaps in what you added at the end about the gametes that live half forever (because the genetic load merges with the genetic load of another individual during mating) there is some solution, maybe the bodies are not supposed to survive forever but only the genetic load in the cells, after the creature has reproduced and the genetic load has multiplied - There is no longer any benefit in continuing to maintain the cells of an old body since many new bodies have been created.

  17. Yogev:
    The earth would not collapse.
    As soon as there was a shortage of resources, the least suitable would become extinct (and not from old age but from lack of suitability).
    The variety that would then be available to the selection of evolution was greater and the chances that it would find a variation with adaptation to the new conditions would increase with it.
    But it's really better that you read what was written in front of you before you respond.

  18. Where the evolution was faster when the age of death is younger or older 😉 ?
    Because if everyone lived to the age of 250 then the earth would fill up and collapse under all the population explosion,
    On the other hand, when mortality is relatively young there is more "space" "time" and "space" to continue it.

    (If they wrote this before me, I apologize in advance)

  19. Ariel:
    I just returned to the computer and I see that you asked a question and even received an answer.
    The answer I would write is similar to that of Or.
    While the bacterium is a single cell and its descendants are cells identical to it, a human has many cells, each specialized in its field.
    The mechanism is much more complex. In each cell some DNA is deactivated and there are even cells that do not contain DNA at all.
    The whole business should work in harmony while transferring and processing within it (in the pipes that are calcified as water pipes are calcified) external materials, containing within it - in symbiotic relationships other creatures and the like.
    A certain part of man is, however, in a certain sense granted eternal life.
    I'm talking, of course, about the sex cells.
    The mechanism used in man to produce the sperm cells is probably similar in reliability to the one that preserves the entire bacterium.
    What the defector said (what a self-congratulation 🙂 ) are also true.
    As a summary and generalization of his words, he says that the fact that the life of a complex body contains different stages in each of which it must function differently adds great complexity.
    Different cells must undergo changes over time and these changes are not necessarily reversible and reversibility is necessary if you want to allow recovery.

    In relation to old age - even if it does not appear in all complex creatures (and as much as I try to come up with examples in my imagination I cannot recall an animal without old age) - its very existence in many of them confirms my claim.
    Beyond that, as mentioned, there is also that part of old age that lowers the quality of the offspring and even reaches a complete cessation of fertility.
    What use is there in all these?
    You prefer option B, but you failed to deal with the counterarguments, nor did you demonstrate even one of its advantages (and the fact that you claim that something is an advantage is not equivalent to demonstrating the advantage)

  20. Ariel, to your question - "Why would a multicellular creature not be able to maintain its cells in the same way?"
    There are multicellular organisms that have a miraculous ability to regenerate. Many invertebrates have this ability, and there are some, such as the Dugesia flatworm, which is able to regenerate even if it has lost two-thirds of its body. You can cut one worm in half, and both halves will replace the missing half. This will result in two genetically identical individuals (like clones).
    Moreover, it is a known way of reproduction of flatworms, and also of other invertebrates such as the hydra. creatures but voluntarily tear their bodies apart in a process called autotomy.

    The bottom line is that the evolutionary process of cell specialization (for different organs and tissues) results in a considerable decrease in the ability to regenerate. This regenerative capacity exists in embryonic stem cells, but does not exist in the adult human. This mechanism may be related to aging - due to the specialization of the cell, the body has difficulty renewing it.

  21. to Ariel

    If I'm not mistaken butterflies don't die of old age and neither do many other insects. You should also check this for plants.
    To strengthen your idea - . In a society where the individuals do not age and always look young, the females will always prefer the older individuals (and the males will also prefer the older females) because they are smarter and more experienced and their ability to survive is generally higher. As a result there won't be much room for genetic variation and this is evolutionarily disastrous.

  22. This is a really interesting article. Go find out what the future effects of the research will be.

  23. I'm all elect engineer, so I don't claim to be a polymer.
    In my opinion, in a multicellular creature like man, the genetic code (like a software code) contains a growth plan (commands). But the growth is not linear and slows down if time, like a sine wave multiplied by an exponent, decays.
    The same exponent fades, the same code that reduces and eliminates the growth, in my opinion, brings with it defects in the production and we are not perfect.
    It may be that the transition from the "growth" state, to the "preservation" state in a living organism, which requires the transformation of many genetic functions from an operating status to an idle IDLE status, did not reach perfection in 3 billion years of evolution.
    Just like there really isn't a perfect digital "0" or "1".

  24. Michael - you do know a machine that does not break down forever - the bacteria that, as you mentioned, with the exception of the case described by Prof. Kolka, are immortal. Why would a multicellular creature not be able to maintain its cells in the same way? Even if whole cells or organelles in cells break down - they can be repaired or replaced.

    It is a fact that no complex creature is immortal, I can interpret this in two ways: (a) There is nothing to do, death is the decree of reality, spoilage, genetic changes and cumulative damage eventually kill the cell. (b) Death has some evolutionary benefit.

    I prefer interpretation (b), I don't have an answer to the question of what benefit there is in decay and old age, on the face of it it seems that a quick death that clears the space for young creatures quickly is preferable.

    It is also necessary to find out whether old age does appear in all creatures in which there is a natural death. It is possible that there can be a natural death without the introduction of old age.

    Another idea that connects to Michael's idea of ​​wear and tear and also to my initial idea: it is possible that there is always wear and tear in the cells of productions and at some point it is no longer "worth it" to repair the cells and it is better for the creature to die and give way to new offspring. Old age is therefore giving up renewal to make room for future generations.

  25. Let it be clear:
    I am sure that death - like our other traits - is inherent in our genes. I didn't say otherwise. I only said that in my opinion there was no positive natural selection of creatures due to their tendency to die of old age.
    The accepted opinion - according to which mechanisms did not develop in us to preserve us beyond the age of childbearing seems much more logical to me.
    The only question for which the consideration raised by Ariel can be relevant is the question of why the fertility of the animals does not continue until long enough, but here it is even more clear that it is an erosion of the systems. In humans, for example, as age increases, so does the tendency to produce defective offspring. What evolutionary advantage could this phenomenon have?
    This is of course a private case of the lack of logic in that death comes gradually and is preceded by old age. What evolutionary advantage does this fact bring?

  26. to Ariel
    I agree with your opinion
    It is true that increasing the birth rate increases the possible mutations for passing on to the next generation, and will of course help the species in the future to overcome the new difficulties in its environment, but on the other hand it decreases the resources shared between a larger group of individuals. That's why we have a need here to look for the optimum for the development of the species, that's why I believe that death is demanded in our genes.
    Good Day
    Sabdarmish Yehuda

  27. Ariel:
    It doesn't belong because more suitable mutations will overcome the less suitable creatures regardless of the stage they were born.
    Death results in total changes in the size of the population and in this sense there is no difference between the population of the new generation and the population of the old generation. On the contrary - the population of the old generation corresponds to reality with a higher probability because it has proven to have survived until now. As soon as there is a change that this population is not built to deal with, it will become extinct anyway.
    If the size of the population was such an important factor, it would also limit the birth rate (again - to reduce the competition between the carriers of the competing genes).
    As a principle, there are situations where it is better for a part of the population to die, but it is not at all clear in advance which part is better for it to become extinct, and the only way to determine this in an optimal way is to let natural selection take its course according to the traits and without considering the generation of origin.
    The example of the bacteria proves this well because these are the creatures with the highest survival capacity (as a species) and their evolution defeats all new technological innovations.
    It is true that there are situations in which the colony of bacteria decides to "organize" collective suicide of some individuals, but even then it is not aging.
    In reality, I don't know of any machine that never breaks down, and therefore the accepted hypothesis that over time things simply break down seems to me more reasonable than the possibility that survival requires a death sentence for adults - especially, as mentioned, when this possibility is disproved by the best survivors.

  28. Yeshaya Abed Hashem: What a beauty, thank you very much, I actually studied one course with Professor Hana Engelberg-Kulke, maybe she mentioned it in one of the lectures.

  29. Ariel – Here's a hint about the referral you're looking for.
    A group of Hebrew University scientists headed by Prof. Hanna Engelberg-Kulka of the Department of Molecular Biology at the Hebrew University - Hadassah Medical School have discovered a new bacterial communication factor. The researchers revealed the discovery of the extracellular death factor, and described some of its characteristics and several genes that are involved in its generation in an article published in the October 2007 issue of Science magazine.

  30. Michael:
    I know that bacteria do not die a natural death but undergo binary division, this does not contradict my idea in general, it can only show that it is not appropriate in all cases. Besides, I'm not XNUMX% sure that there is no planned death in prokaryotic organisms, as far as I can remember there is a finding showing that bacteria can signal each other to die when environmental resources run out. No, I don't have a link to the article.

    Now try to show with the help of logic that the idea itself is not true, my idea is simply this: in organisms that have a genetically planned death after a certain time/number of divisions, the rate of genetic changes increases and their chances of adapting to a changing environment also increases.

  31. Ariel:
    It is possible to prove that your words are not true also through logic, but it would be a long and complex story, so I prefer to refute them with a simple finding:
    The bacteria do not die of old age.

  32. Do the genes ELT-3, ELT-5 and ELT-6 also affect the Hutchinson-Gilford Progeria syndrome (the aging child syndrome)

  33. To my father

    Are the ELT-3, ELT-5 and ELT-6 genes also associated with Hutchinson-Gilford Progeria syndrome (the aging child syndrome)?

  34. exciting,
    I thought that aging was due to the shortening of the telomeres at each cell division,
    Until the cell is formed that cannot divide further, then the death of the cells causes the effects of aging.

    Every day there is a new theory on these issues,
    Guess the full truth will be revealed when all or some of them are exposed.

  35. And I have a slightly different idea, aging is the way for species to increase their genetic variation, aging and the resulting death decrease the mature part of the species' population, therefore increasing the ability of the young part of the species' population to survive and reducing the competition within the species between young and mature individuals , and therefore the competition between a species that has death mechanisms and other species is more effective.

    My wording is not sharp enough, but I hope the idea is understood. I would appreciate comments and corrections.

  36. Until today they said that aging is the result of the accumulation of mutations. They didn't say maybe, they didn't say there was no proof, and the statements sounded quite firm. The phenomenon of statements of this kind relaxes the collective mind to think and find the truth... except for a few trailblazers and convention breakers.
    A bit reminiscent of the medical recommendations regarding nutrition - every time they change and change what is allowed and what is not recommended to eat.

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