The virus and the cell

The deeper into evolution you get, the more an uncanny feeling of continuity grows. This is especially true when considering viruses and the origins of life. On some level it is easy to think of a virus as a pre-cell; it is smaller, more compact, in some ways simpler. But without a cell, and without access to the extensive machinery required for replication and release of its progeny, the virus is as dead as a ping pong ball floating through space. So while it’s easy to think of evolution linearly – that over time life has grown more and more complex – I think it more likely that the virus came from us, or whatever we were back then (maybe a simple unicellular prokaryote).

Our cells make virus-like particles all the time – little packets of membrane and genetic information which can be taken up by neighboring cells. These exosomes can go a long way along the spectrum of what we think of as self sustaining or infective. Some are just little blebs of membrane and cytoplasm, harmless and useless. Some contain messenger RNA, which when taken up by a neighboring cell will instruct it to make more of this or that protein. Is it a bridge too far to think one of these messenger packets might have gone rogue, carrying instructions for the hijacking of the next cell, instructions for the endless propagation of self?

When you accept the intertwined nature of our fates, the fossils of viruses start popping up all over our own genome. These artifacts are in every cell in our body – approximately 8% of our genome consists of retroviral DNA, genetic information which was stuck in during some ancient infection and has been passed down generation to generation. There’s the Arc protein found in neurons, which could have been co-opted from an ancient virus to allow for better intracellular signaling. There is the HAP2 protein of sperm, which looks an awful lot like a protein many viruses use to invade cells. This protein is so ancient it is found in all living things that mix up their genetic information through gamete fusion, including plants, animals, and parasites such as malaria’s causative agent, P. falciparum. When you take a step back, the two processes are similar – both the sperm and the virus need to breach a cell, inserting its own DNA. Is it possible that the origins of this process resembled a virus invading a cell, and was only later co-opted for the purposes of genetic mixing?

When you disappear down this rabbit hole, viruses start to feel like extensions of us. They’ve intermingled in our genetic ancestry almost since the beginning, giving and taking some of our best biological innovations. Evolution is a tangled web, affected both by our surrounding environment and by the viruses we’ve caught.


An intervention

I’m reclaiming my blog. I’ve fallen into the hole of high expectations: that I’ll blog only short, persuasive, well reasoned pieces, which I will never have any reason to feel embarrassed about or have to defend as the logic will be flawless and absolutely indisputable.

That logic is what turned this space into a pretty quote mill, and then a ghost town.

So I’m putting a new stake in this space! What are blogs really good for? Trying out ideas. Fleshing out thoughts. Having conversations. Practicing quantity, speed, and completeness. That’s the goal.

I am, personally, very much in the writing as thinking camp. Since I’ve retreated from the public-private space of a personal blog to the private-private space of a personal journal, my thinking has become more and more half-baked. This sort of public space requires more thought, review, and editing.

But it’s still for me. So I’m opening myself up here, allowing the far-less-than perfect writing out onto the internet.

Happy New Year!

Quote of the Day

There is no need to be frightened. It is true that some of the creatures are odd, but I find the situation rather heartening than otherwise. It gives one a feeling of confidence to see nature still busy with experiments, still dynamic, and not through or satisfied because a Devonian fish managed to end as a two-legged character with a straw hat. There are other things brewing and growing in the oceanic vat. It pays to know this. It pays to know there is just as much future as past. The only thing that doesn’t pay is to be sure of man’s own part in it.
-Loren Eiseley, The Immense Journey

Quote of the Day

A writer should concern himself with whatever absorbs his fancy, stirs his heart, and unlimbers his typewriter. I feel no obligation to deal with politics. I do feel a responsibility to society because of going into print: a writer has the duty to be good, not lousy; true, not false; lively, not dull; accurate, not full of error. He should tend to lift people up, not lower them down. Writers do not merely reflect and interpret life, they inform and shape life.
-E.B. White

Quote of the Day

It has been frequently remarked that it seems to have been reserved to the people of this country, by their conduct and example, to decide the important question, whether societies of men are really capable or not of establishing good government from reflection and choice, or whether they are forever destined to depend for their political constitutions on accident and force.
-Alexander Hamilton, Federalist No. 1