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As a layman I'm kind of baffled by the enduring pop-sci interest in mitochondria. To me the far more interesting organelle is the ribosome. This elegant self-
by Teever 2y ago
As a layman I'm kind of baffled by the enduring pop-sci interest in mitochondria.
To me the far more interesting organelle is the ribosome. This elegant self-replicating machine that is highly conserved across lifeforms is fascinating and much closer to the origin of life than mitochondria.
How did ribosomes evolve? Are the ribosomes that we see in modern organisms the first design that did evolve? Why are they highly conserved?
Are ribosomes alive as well?
- dangsux 2y ago[dead]
- adastra22 2y agoThe mitochondria and their dysfunction are likely the basis of most aspects of aging, so an intensive interest in them is understandable.
- GordonS 2y agoAlso thought to be involved with Chronic Fatigue Syndrome (CFS/ME).
- Teever 2y agoThat's a debatable statement and it doesn't explain the public appeal of mitochondria over ribosomes that predates recent research on the relationship between mitochondria and aging.
- adastra22 2y agoWhy are you insisting on this comparison to ribosomes? They’re both interesting.
- rbanffy 2y agoAll organelles are valid. This is not a competition. Both mitochondria and ribosomes are cool in different ways.
- Teever 2y agoI'm just wondering why we always see pop-sci mitochondria content but no ribosome videos. I think it's the catchy nickname "powerhouse of the cell." Ribosomes don't have a catch nickname so they get a lot less content produced about them. If I was a highschool biology teacher I'd probably call them "The assembly line of life." That would stick in people's minds I bet.
- olddustytrail 2y agoThen go ahead. Make those videos. Sell that vision. There's no one stopping you except you.
- Teever 2y agoI don't get the adversarial tone about this. My intention in asking the question isn't to create animosity. I'm just curious why the thing that I've observed is a thing.
- adastra22 2y agoBecause bringing up “what about Y?” When the discussion topic is X and there is no connection to Y goes against HN norms.
- Teever 2y agoBut there is a connection between the X and Y in this case. One is a subset of the other. We're talking about the same thing man, I'm just making the point that I feel that there should be greater emphasis on the subset. Look at the top thread in this post, people are doing a very similar thing. I truly think that the pop-sci interest in mitochondria stems from the nickname and for no other reason and to me that's a very interesting thing.
- adastra22 2y agoRibosomes and mitochondria are not the same thing.
- lostemptations5 2y agoIt's interesting, could you expand on thus?
- adastra22 2y agoIt's actually a collection of theories known as the mitochondrial theory of aging: https://en.wikipedia.org/wiki/Mitochondrial_theory_of_ageing https://en.wikipedia.org/wiki/Mitochondrial_theory_of_ageing It's a little confusing to look into, because there's a bunch of separate theories about the nature of aging that all involve mitochondria in some way. You will find news articles saying that the mitochondrial theory of aging was discredited because of some study done, but when you look into it, it turns out that what was shown was that some specific variant of the theory was insufficient for accounting for all forms of aging, which is not the same thing. Each mitochondrial theory of aging is a theory about one pathway by which mitochondrial function or dysfunction results in aging damage, the reality is that many or all of these theories are true and aging is the aggregation of damage from all of them, and more pathways we have yet to discover. Generally speaking, the vast majority of aging damage comes, directly or indirectly, from the accumulating damage from healthy operation of mitochondria over long periods of time, or the accumulation of cells with unhealthy mitochondria that produce damage more rapidly. The ELI5 is that mitochondria produce free radicals, free radicals chemically alter basically anything they touch, and aging is simply the slow accumulation of intercellular and intracellular damage, and if you follow the history of these molecules back to when they diverged from being in a healthy state, it is almost always the result of oxidative damage (e.g. free radicals of the sort produced by mitochondria). Another ELI5 way of looking at it: you may not know this, but mitochondria only live a couple of days. They are constantly being refreshed in your cells because of the severe oxidative stress they undergo. They also sometimes break or leak, letting those reactive oxygen species into the cell and causing damage. Aging is the accumulation of this damage. But I said aging was "downstream of" mitochondrial dysfunction. That's because not all aspects of aging is due to reactive oxygen species leaking out like I seemed to claim above. That's just one example. There are cells in your body that have lost all mitochondria, often due to a freak genetic mutation in the mitochondrial DNA of that cell. Surprisingly these cells don't die, but rather switch into a mode of operation where they slow down and live off energy extracted from the intercellular medium and converted into ATP by various molecular systems embedded in the cell membrane. These processes, as it turns out, free radicals out of the cell during operation, spewing reactive species into the body. This ends up being responsible for hardening tissue, lack of energy, and many other symptoms of aging. But the root cause? The mitochondria stopped working in that cell, so still a mitochondrial issue. Or, the aging of heart cells and the hardening of arteries is largely due to the collection of dysfunctional lysosomes that are full of garbage they are unable to break down. These clutter cells, harm their efficiency, and eventually have enough collective effect as to make the tissue as a whole less viable. Leading to heart attacks and other cardiovascular disease, which is the leading cause of age-related death alongside cancer. Want to guess what these defective lysosomes are full of? Mostly undigested mitochondria, specifically the highly damaged structures of mitochondria that suffered too much oxidative damage from long operation. Oh, and what about cancer? Well cancer needs A LOT of energy to keep replicating, and so it should be no surprise that many of the mutations among common cancers have to do with genes in the nucleus affecting mitochondrial function, or the various signaling pathways between the nucleus and the mitochondria of the cell. This article covers some of the ways that cancer uses mitochondria: https://pmc.ncbi.nlm.nih.gov/articles/PMC4371788/ https://pmc.ncbi.nlm.nih.gov/articles/PMC4371788/ The best lay introduction I know is "Ending Aging" by Aubrey de Grey and Michael Rae. The book is meant to be an enumeration of all the things that need to be done to biologically reverse aging, but ends up being more than 80% about mitochondria and mitochondrial dysfunction, because of its out-of-proportion impact on the aging process.
- dist-epoch 2y agoTodays ribosomes are not alive by any definition. But it's possbile they are descendants of some self-replicating self-catalyzed RNA chain (RNA world)
- jamiek88 2y agoThey are both very interesting. I don’t think there’s necessarily interest in one are the expense of another?
- francisofascii 2y agoMitochondrial health is considered a strong proxy for overall health.
- gus_massa 2y agoRibosomes are much smaller than mitochondria. Moreover, mitochondria have a lot of ribosomes inside that they use to make their own proteins. https://en.wikipedia.org/wiki/Mitochondrial_ribosome https://en.wikipedia.org/wiki/Mitochondrial_ribosome > Are ribosomes alive as well? Nah [1]. They do single task. They just read RNA, pick amino acids [1] and make proteins. If a cell were your house, it's like a 3D printer. Mitochondria are much bigger, they have their own DNA, they reproduce, have a lot of internal structure, they do all the task of a normal cell. If a cell were your house, it's like having a bunch of squirrels trained to wind the clocks in exchange for peanuts. [1] The definition of alive is complicated, so I prefer a "Nah" instead of a super hard "No". [2] There are some details I'm hiding, like mRNA, tRNA and even rRNA.