
A Eukaryote Without a Mitochondrial Organelle - okket
http://www.cell.com/current-biology/abstract/S0960-9822%2816%2930263-9
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hammock
_> The complete absence of mitochondria is a secondary loss, not an ancestral
feature_

Basically the organism evolves to not need its mitochondria, replacing it with
a different system.

The story goes that mitochondria used to be separate organisms (they have
their own DNA) living in symbiosis with other cells, and eventually being
subsumed.

So this would be an example of an organism similarly evolving to incorporate a
bacterial symbiotic relationship (as opposed to what the mitochondria
provide). Not surprising to me that this is possible, or that we eventually
found something like this, given that this is how mitochondria came to exist
in cells to begin with.

I was hoping that we would have found an organism that existed before
mitochondria were subsumed into cells. That would be cool

~~~
Ericson2314
To be clear, this is a lateral gene transfer from bacteria, which doesn't
necessitate previous a symbiotic relationship with that bacteria, right?

~~~
rdancer
Mitochondria are self-contained organelles. Gene transfer would be if their
DNA became part of the nuclear DNA. What you suggest is that there was first a
lateral transfer, and then that transferred DNA was ejected from the nucleus,
and the cell somehow formed organelles that look surprisingly like bacteria.
The theory I believe is that symbiosis evolved into mutual dependency, with
the mitochondria starting to live inside the cells instead of outside them
sometime along the way.

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rwmj
I can definitely recommend "Molecular Biology of the Cell", which is a
undergrad-level textbook about cells. The latest edition is always very
expensive, but you can get older versions cheaply. Link:
[https://www.amazon.co.uk/gp/product/0815341067](https://www.amazon.co.uk/gp/product/0815341067)

~~~
fdej
I've been reading another textbook on the same topic recently, and find it
endlessly fascinating. I can grok quantum mechanics intuitively on some level,
because it's governed by simple mathematical laws, even if those laws are
quite different from everyday experience of how physical objects work.
Understanding how ordinary matter (atoms, molecules, then solids and fluids)
forms out of fundamental interactions is, in principle, just a matter of
solving for N variables, and you can use statistics when N gets large. But the
complexity of how life exploits the precise interactions between thousands of
different molecules to assemble complex machines, on scales from single
proteins to whole organisms, involving thousands of interconnected feedback
loops to sustain the process and counteract the large-N averaging effect of
the second law of thermodynamics, is just mind-boggling.

If you're a programmer and think 10 million lines of code constitutes a
complex system, reading about how cells work on a molecular level should be
humbling.

~~~
sn9
If you've got a physics background, you might also enjoy _Physical Biology of
the Cell_ [0].

I haven't read it personally, so I can't vouch for it, but I've seen it
recommended as one of the go-to texts for those interested in the biophysics
of cells.

[0] [http://www.amazon.com/Physical-Biology-Cell-Rob-
Phillips/dp/...](http://www.amazon.com/Physical-Biology-Cell-Rob-
Phillips/dp/0815344503/ref=pd_sim_14_36?ie=UTF8&dpID=51B-wJKEMsL&dpSrc=sims&preST=_AC_UL160_SR123%2C160_&refRID=1MK218JD2X3HACH3WCHV)

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gmisra
For those in search of a succinct summary of the science:
[http://www.sciencemag.org/news/2016/05/first-eukaryotes-
foun...](http://www.sciencemag.org/news/2016/05/first-eukaryotes-found-
without-normal-cellular-power-supply)

~~~
Amorymeltzer
FWIW —
[https://news.ycombinator.com/item?id=11684595](https://news.ycombinator.com/item?id=11684595)

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DiabloD3
I find it funny sometimes that we bitch about genetic manipulation in weird
ways, but the Random Number God (RNG) pulls this one out of it's hat and does
something rather unique and surprising.

~~~
x5n1
If it can be done, it will be done. Mitochondria is a pita, so sure some
enterprising cell decided to figure out a way to do without it and it did.

~~~
viewer5
> Mitochondria is a pita

What's troublesome about mitochondria?

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gherkin0
Free-radicals?

[https://en.wikipedia.org/wiki/Free-
radical_theory_of_aging#M...](https://en.wikipedia.org/wiki/Free-
radical_theory_of_aging#Mitochondrial_theory_of_aging)

~~~
marcosdumay
You'll get those in any respiration cycle based on oxygen.

Mixing extremely reactive substances will destroy something. It's better to
just deal with it, and reconstruct whatever is damaged - the path our body
tries hard to take.

