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CRISPR-like ‘immune’ system discovered in giant virus
- bitwize 11y agoGetting a look at that mimivirus makes me think whatever gets infected by it failed its saving roll.
- haberman 11y agoI think you mean "role", though I love the image of a virus rolling a d6 to determine whether it succeeded or failed.
- marshray 11y agoWhat, did you see the picture? That virus is literally a D20.
- dnautics 11y agopretty much all virii are "D20"s.
- marshray 11y agoReally? The pictures I've seen of ebola make it look like spaghetti.
- Amorymeltzer 11y agoYou're quite right, GP is being mistakenly over-broad. Mimivirus (APMV) is an encapsidated virus, and the capsid is what forms that shape. Capsids[1] generally contain the DNA or RNA of the virus' genome and often appear quite geometric. Capsids have a T-number, which determines how many faces of triangles or hexagons+pentagons exist. It's a deeply mathematical field of study since these are, essentially, tiny repetitive building blocks. Some (tobacco mosaic virus being the most famous) are helical, while others (bacteriophages) look completely different[2]. Viruses appearing spherical are generally enveloped, meaning they contain part of the cellular plasma membrane surrounding their capsid (HIV). Ebola is part of the filovirus family[3], which are characterized by, among other things, their long, filamentous shape (hence the name). 1: https://en.wikipedia.org/wiki/Capsid https://en.wikipedia.org/wiki/Capsid 2: https://en.wikipedia.org/wiki/Bacteriophage https://en.wikipedia.org/wiki/Bacteriophage 3: https://en.wikipedia.org/wiki/Filoviridae https://en.wikipedia.org/wiki/Filoviridae
- tallerholler 11y agothis is fascinating... makes me want to go back to school and study viruses (what field would that be?)
- ridgeguy 11y agoVirology, I believe.
- dnautics 11y agoBacteriophages are often icosahedral in the headpiece. In fact, the packing motor portion of the icosahedral bacteriophage was not solved until recently because the symmetry averaged structure washed out the stalk part in crystallography and cryo-EM techniques. (it was machine-vision-assisted cryo-EM class averaging technique that helped elucidate the structure) Yes, there are some filamental viruses such as TMV and ebola, and the P22 bacteriophage, but most viruses, even membrane-enveloped ones, seem to have icosahedral or pseudo-icosahedral structures. My original point being: "d20"-ness is the rule, not the exception.
- harshreality 11y ago"Virii" isn't a generally acceptable plural form of "virus", and was only really a thing because the insular 90's hacker community started using it to refer to computer viruses. https://en.wikipedia.org/wiki/Plural_form_of_words_ending_in_-us#Virus https://en.wikipedia.org/wiki/Plural_form_of_words_ending_in...
- abecedarius 11y agohttps://en.wikipedia.org/wiki/Capsid https://en.wikipedia.org/wiki/Capsid doesn't seem to say which ones are d12's, but it's in the list! Pretty neat.
- dnautics 11y agothe d12 ones are effectively equivalent to d20s because an icosahedron is the dual solid of the dodecahedron; depending on "how you look at it", T1 virus capsids can either be "d20s" or "d12s".
- msie 11y agoI think "roll" is the right term. You "fail" the roll of the die, you get infected.
- bitwize 11y agoD&D is a role playing game, but you roll the dice to see what happens.
- alariccole 11y agoReally makes you wonder if viruses were the first forms of life, contrary to popular opinion.
- venomsnake 11y agoNo. The viruses were probably the second. You need some form of self replicating metabolism, before having a virus to be able to feed on it.
- mc808 11y agoI would imagine the earliest forms of life (proto-life if we use cellular structure in the definition of life) were free-floating strands of genetic material, more similar to viruses than to fully formed cells. Or if that's on the right track, we could say the first "cells" were large bowls of the primordial soup.
- therein 11y agoTake a look at the videos at this link. (the ones showing the fatty acids holding onto each other) http://exploringorigins.org/fattyacids.html http://exploringorigins.org/fattyacids.html
- danjayh 11y agoFascinating article, but it was hard for me to get past 'Immune defence'. I'm sure they meant no offence, but it coloured the rest of the text for me. (If it had been on a .co.uk, I'd have left them alone, scout's honour).
- millettjon 11y agoThere is a related Radiolab episode: http://www.radiolab.org/story/shrink/ http://www.radiolab.org/story/shrink/