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Mitochondria are fascinating, and it seems probably very very old too! Nick Lane (http://www.nick-lane.net/) writes a lot about the subject in;

https://www.amazon.co.uk/Power-Sex-Suicide-Mitochondria-mean...

https://www.amazon.co.uk/Vital-Question-Why-life-way/dp/1781...

it is talked about a bit in The Vital Question [1] and a more in depth in Power, Sex, and Suicide [2]

His books are honestly life changing, i can recommend them or him enough.

[1] https://www.amazon.com/Vital-Question-Evolution-Origins-Comp...

[2] https://www.amazon.com/Power-Sex-Suicide-Mitochondria-Meanin...

⬐ neom

Thank you.

This book did a great job, but it might be outdated:

https://www.amazon.com/Power-Sex-Suicide-Mitochondria-Meanin...

⬐ Symmetry

In another of Nick Lane's books he mentions compatibility between nuclear and mitochondrial DNA as a possible reason for variation in fertility in different species. If that's true I'd expect the 3-parent process to produce fewer pregnancies per fertilized egg than the normal 2-parent method which runs at around 50%.

⬐ misiti3780

which book was that ? Life Ascending?

⬐ Symmetry

That's what I was thinking, so if you think so too then probably.

The public perception of evolution misses out on the depth of scientific work being done these days. Two more books that make modern evolutionary research accessible to the public:

1. Nick Lane's Power, Sex, Suicide: Mitochondria and the Meaning of Life - Covers the evolution of the eukaryotic cell, why it's such insanely chance event, why multicellular life depends on it, almost as an aside making a great argument that complex multicellular life is extremely rare in the universe. Also has a couple of fascinating chapters on how the interaction of the mitochondrial genome with the nuclear genome influenced development of sexes and sex.

http://amzn.com/0199205647

2. Nick Lane's Life Ascending: The Ten Great Inventions of Evolution - Covers very different material and again all fucking fascinating. It's amazing to see how things like sight have evolved over and over and over because they're so fucking useful, and the genetic analysis that allows us to pick out each separate emergence of a feature.

http://amzn.com/0393338665

What I find interesting about aspirin is that no one really knows how it works (its "mechanism of action"). Its anti-inflamatory effects are a consequence of something else, not the cause.

In the book "Power, Sex, Suicide"[1], Nick Lane states:

"Curiously, aspirin is also a mild respiratory uncoupler; I do wonder how many of its more mysterious benefits may relate to this property"

He is talking about the mitochondrial respitarory chain. In this context, "uncoupled" means that the electron flow does not generate any ATP; instead, all the energy is dissipated as heat. The interesting thing is that uncoupling the electron transport chain reduces electron leakage ("free radicals") and less free radicals has been associatted with ageing and disease.

Will less electron leakage reduce chronic inflamation ? Who knows ...

Once again, the analogy with computer systems is pretty straightforward: If our back-end system is "inflamed" (read, under heavy load) due to incoming HTTP requests, uncoupling it with a message queue system will have anti-inflammatory effects.

[1] http://www.amazon.com/Power-Sex-Suicide-Mitochondria-Meaning...

[2] http://sciencecases.lib.buffalo.edu/cs/files/dinitrophenol.p...

⬐ atmosx

Aspirin is very well understood, Wikipedia has a very extensive article about how it works. It's a pro-drug, when activated takes a place. Search for Arachidonic Acid pathway if you are interested.

Also, By binding free radicals ( a we'll know, side-effect of aspirin and Vitamin C) you get less chances of getting cancer for one.

⬐ fasteo

I meant that the known mechanisms do not explain all its reported benefits. In the Wikipedia article that you mention this is clearly stated:

"However, other effects of aspirin, such as uncoupling oxidative phosphorylation in mitochondria, and the modulation of signaling through NF-κB, are also being investigated."

⬐ robbiep

Hi there,

I think you need to explain yourself a bit better - you have made a statement that is demonstrably false, at least in the sense that you have used it -

aspirin is that no one really knows how it works

- Aspirin works by a very well understood mechanism of binding irreversibly to the COX enzyme, with a preference for COX1 over COX2. there is no debate about this.

Thankyou for pointing me down the rabbit-hole regarding uncoupling and the decrease in free radical production this creates [2], something I was not previously aware of

[1] Uncoupling of intestinal mitochondrial oxidative phosphorylation and inhibition of cyclooxygenase are required for the development of NSAID-enteropathy in the rat doi/10.1046/j.1365-2036.2000.00723.x/

[2] Mitochondria and reactive oxygen species 10.1016/j.freeradbiomed.2009.05.004

⬐ fasteo

Indeed. Wording is important.

I meant that the known mechanism that you have mentioned does not explain all its reported benefits. Specifically in the anti-inflammatory effect, it seems like inhibition of prostaglandin synthesis (via COX enzyme binding) is not the reason[1].

As aspirin has so many potential benefits, it seems to me that it has to have some effect in some very basic and common site and the mitochondrial respiratory chain is a good, if not best, candidate.

If you are interested in uncoupling and free radical production, Peter[2] has a good amount of info about it.

At any rate, aspirin has many knowns unkowns; that´s what I meant in my original post.

[1] http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2213311/

[2] http://high-fat-nutrition.blogspot.com.es/

⬐ robbiep

Thanks for pointing me to that blog, really interesting stuff. Rob

The fact that relatively high intelligence has arisen from many architectures multiple times on this planet bodes well for the frequency of intelligent life on exoplanets.

As I remember from the book "Power, Sex, Suicide: Mitochondria and the Meaning of Life" [1], the bottleneck may be not the evolution of the intelligence, and not even of life itself, but specifically multicellular life. There are reasons to believe it only happened once, and for about 1bn years before that life already existed in single-cellular form, which gives an idea on how improbable the step from single to multiple cell organisms is. I am vague on specifics though, but can wholeheartedly recommend a book to anyone interested in evolution and origins of life.

[1] http://www.amazon.com/Power-Sex-Suicide-Mitochondria-Meaning...

⬐ thisjepisje

I'm no expert, but in my understanding the transition from unicellular to multicellular can go pretty smoothly via symbiosis.

⬐ Evgeny

Actually, I stand corrected - not the multicellular life evolved once, but the eucaryotic cell. According to the book, eucaryotic cell evolved by acquisition of mitochondria. Energy generated by mitochondria allowed the eucaryotic cells to be much bigger than procaryotic ones, and to support multiple different organelles.

⬐ civilian

Yup! The formation of the first Eukaryotic cell is a mystery. Eukaryotes have features of both bacteria and archea, yet doesn't have a clear origin in either of them. Here's a book that goes into more depth on the important stages of evolution: http://www.amazon.com/Major-Transitions-Evolution-Maynard-Sm...

On a tangent, my dismissiveness of creationists has only increased since reading The Major Transitions in Evolution. There are some really perplexing things in early evolution that we don't understand at all. And yet creationists like to talk about chimps and rocks.

⬐ Evgeny

Here's a book that goes into more depth on the important stages of evolution

And the Kindle edition is more expensive than the paper one ... makes me wonder how their pricing process works?

⬐ detroitcoder

Just bought it! Thanks

⬐ SergeyHack

According to an interesting book of a Russian paleontologist Kirill Eskov [1] there were a lot of "evolutionary tries" to create a multicellular life. And as soon as it became "profitable" the regular try conquered the world.

IIRC it was related to increased oxygen level.

[1] "История Земли и жизни на ней" ("History of the Earth and its lifeforms")

So what is it that they have in place of mitochondiria?

A fascinating book "Power, Sex, Suicide: Mitochondria and the Meaning of Life" (http://www.amazon.com/Power-Sex-Suicide-Mitochondria-Meaning...) suggested that the multicellullar organisms on Earth evolved only once, when the symbiotic relationship between two types of bacteria was formed - one of them became "host", and the other became mitochondria and specialized for energy production.

The book suggests that the conditions for this to happen were very unusual and are unlikely to ever happen again. It does even suggest that this may mean that life in the Universe, more complicated that single-cell organisms, is very unlikely to evolve.

If eukaryotes evolved more than once, then there's some more hope for extraterrestrial life I suppose ...

⬐ etal

They use hydrogenosomes, or something similar, instead:

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

It looks like the metabolic reaction is somewhat similar to the aerobic one used by mitochondria, but uses hydrogen ions instead of oxygen molecules. Hydrogenosomes may or may not be evolutionarily related to mitochondria.

Here's the original journal article (open access):

http://www.biomedcentral.com/1741-7007/8/30/abstract

⬐ eru

> If eukaryotes evolved more than once, then there's some more hope for extraterrestrial life I suppose ...

Wouldn't you call extraterrestrial bacteria `life'?

⬐ netcan

Well, most people think multicellular when they get excited about life because multicellular is how earth life gets complex. To that end eliminating flukes that happen only once is important.

⬐ eru

OK. I am not that discriminating. (Actually, Archae and Bacteria are much more interesting too me.)