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  • [♪♩INTRO]

  • Of all the cells in the human body, fat cells might get the most hate.

  • Their main function is to store fat molecules.

  • And while that is a very important job, a lot of people kinda maybe wish they didn't

  • have quite so many.

  • But it turns out that fat cells, or adipocytes, are doing a lot for your body -- maybe even

  • more than scientists ever imagined.

  • Because this week, a trio of British biologists reported for the first time that fat cells

  • can move.

  • Oh, and also it turns out they help heal wounds.

  • The study, which was published this week in the journal Developmental Cell, was done on

  • fruit flies.

  • But the team thinks fat cells might do something similar in humans.

  • The researchers were interested in how fruit flies repair their wounds, and there were

  • some hints that fat cells could be involvedlike weirdly big shadows that showed up

  • under a microscope.

  • For these experiments, they used lasers to make small wounds on the underside of fly

  • pupae — I know this seems kind of meanthat's the stage just before the fly is fully grown.

  • And to keep track of which cells were fat cells and which were other types, they turned

  • them different colors.

  • Then they recorded what happened next under a microscope.

  • Almost immediately, large fat cells started traveling to the injured area to plug the

  • hole, usually taking about an hour to get there.

  • Then they basically turned into, like, a fat version of a band-aid, forming a tight seal

  • on the wound that would keep bacteria out.

  • The fat cells also worked with the flies' immune system to remove dead cells and any

  • other debris that was hanging around.

  • And if the researchers infected the wound

  • on purpose, the fat cells released antimicrobial peptides, or small defense proteins, to fight

  • them off.

  • Seeing fat cells help heal wounds was weird enough.

  • But really, the strangest part was the fact that these cells were moving at all.

  • Researchers had always assumed fat cells kind of just sat there.

  • But here was a cell swooping in to save the day.

  • It gets even weirder, because the fat cells weren't moving the way most cells in an

  • organism do, which is by sticking to other cells and tissues and kind of pulling themselves

  • along.

  • Instead, the fat cells seemed to be entirely on their own, changing their shape to propel

  • themselves through the flies' liquidy insides.

  • Basically, they were swimming.

  • Now, the question is whether we also might have a bunch of Michael Phelps-like fat cells

  • in us that mobilize when we get hurt.

  • Obviously, there's a lot going on in flies that's different from humans.

  • We have much more complicated clotting systems, so it's unlikely fat cells would serve the

  • exact same purpose in us as in flies.

  • And hopefully not too many of us are suffering from laser wounds.

  • But there's some evidence that fat cells in mice also pump out these antimicrobial

  • defense proteins, which could bode well for us.

  • And frankly, no one has looked very hard to see whether any fat cells are moving.

  • So, it could be just a fly thing, but it might not be.

  • And maybe you should be thanking your fat cells, instead of wishing they were smaller

  • or less numerous.

  • Speaking of size:

  • In another paper published this weekthis one in Nature Communications — a group of

  • French and Brazilian virologists reported discovering two new giant viruses.

  • Giant viruses are still microscopic.

  • You're not going to spot any crawling around in your basement.

  • But compared to the rest of the viruses on the planet, these things are hugethey're

  • more like the size of bacteria.

  • And so are their genomes!

  • Since both of the new viruses were found in Brazil, the researchers named them tupanviruses,

  • in honor of Tupã, the thunder god of a local indigenous group known as the Guaraní.

  • One came from the mud of a soda lake — a type of lake that's super salty and has

  • a high pH.

  • So as tasty as it sounds, you probably don't want to drink it unless you enjoy bleach with

  • a side of salt.

  • The other virus was found in deep ocean sediments off the coast of Rio de Janeiro, dug up by

  • a helpful submarine robot.

  • Under a microscope, the viruses look a bit like fuzzy light bulbs with extra long screw

  • sections.

  • They can grow to more than 2 microns, or millionths of a meter, making them one of the longest

  • viral particles on record.

  • Now, usually, viruses have just a handful of their own genes, because they mooch off

  • their hosts for everything else.

  • Influenza A, for instance, has just 8 genes, and HIV has 9.

  • Their entire genomes are made up of less than 15,000 nucleotide building blocks.

  • But these tupanviruses have genomes that are a hundred times bigger, with about 1.5 million

  • of those building blocks making up a whopping 1300-1400 genes.

  • Even more impressive is the content of those genes.

  • Tupanviruses have more genes dedicated to synthesizing and assembling proteins than

  • any virus we've ever seen, including roughly 200 other giant viruses.

  • Which is surprising, because part of what makes viruses dependent on other life forms

  • is the fact that they rely on their hosts for that very job.

  • Now, tupanviruses still can't string proteins together on their own because they're missing

  • a few key players.

  • But almost all the pieces are there.

  • The question is, where did this strange set of genes come from?

  • One possibility is that giant viruses started off as some kind of cell, and then lost some

  • genes over time to become a virus.

  • But it could also be that they started off as smaller viruses, and grew bigger as they

  • picked up genes from various hosts.

  • Scientists are hoping to figure out how giant viruses evolved by comparing their genomes

  • to other viruses and other organisms.

  • The tupanviruses give us a bunch of new data to add to the pile, but they aren't enough

  • to give us the answer own their own.

  • We'll need to find more giant viruses to figure out what really happened.

  • So here's to more digging!

  • About a year ago, we launched a new channel with the help and guidance of our SciShow

  • patrons: SciShow Psych.

  • Well, this coming Tuesday, SciShow Psych turns one-year-old and we would like to celebrate

  • with you.

  • As a thank-you to our patrons, we'll be having a birthday livestream for SciShow Psych

  • on Tuesday, March 6 at 3pm ET.

  • I'll be there, along with my co-host on SciShow Psych, Brit Garner, and a few of our

  • favorite behind the scenes folks as well.

  • And if you're a SciShow patron, we hope you can be there too!

  • Watch for the link to the livestream on Patreon and we'll see you then!

  • Bring your party poppers and your burning psych questions.

  • [♪♩OUTRO]

[♪♩INTRO]

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B1 US fat psych scishow giant microscope livestream

We Just Found Out Fat Cells Can Move!

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    joey joey posted on 2021/05/05
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