Using Gene Editing To Repaint Butterfly Wings

thanks to the great courses plus for supporting PBS Digital Studios how to paint a butterfly wing hey smart people Joe your CRISPR it's a DNA editing technology that you've probably heard about in terms of disease medicine may be making genetically modified organisms but scientists are using it for some really interesting questions like why butterflies have awesome looking wing patterns and how they form so I'm here at George Washington University I'm gonna go CRISPR some butterflies there's been a lot of hype around CRISPR CRISPR but what is it actually CRISPR is a DNA hacking system with two parts and one part is a piece of RNA that carries a set of coordinates matching a specific spot in the genomes DNA the other part is a protein that chews through DNA which creates a small mutation and we can program CRISPR with a specific set of coordinates so it cuts exactly what we want - this red stuff here mm-hmm this is CRISPR tube full of CRISPR every time you hear somebody say Chris Berg now you know what it looks like that's doctor Arnaud Martin dr. Martin and his team are using CRISPR to understand how butterfly genes make so many crazy patterns and colors there's more than 200,000 species of butterflies and moths all with their own unique wing patterns we know they use those patterns to attract mates to hide from predators to send warning signals but how and why these colors get painted that's still a mystery but this is about more than just studying butterfly patterns these scientists are trying to answer an important question about our own biology and even life itself how do the instructions in DNA build body's genes the letters of DNA are just cones how do we go from those letters and codes to the many beautiful shapes and colors that we see in nature this is a question CRISPR can help us answer those of these fundamental basic questions out jeans make shapes this is relevant to us I mean what I want to understand is our dynamics you know people the first step to figuring out the mystery is easy collects and butterfly eggs this is Joe this is also Joe he's a researcher in the lab so we're on the roof of a building in downtown Washington DC in a greenhouse that's why I feel so tropic yeah yeah it's about I think 72 Fahrenheit or something like that maybe a little bit warmer than that and about 85% humidity but the reason that we do that is because we keep gulf fritillary butterflies in if the team is lucky they can collect around 40 eggs a day from these butterflies to modify with CRISPR is one of my favorite butterflies I think they're super pretty yeah we have these lovely silver patches on the underside of that wings which I just think are really really beautiful so you you wait for these butterflies to lay and not through the eggs and and then you collect them to do the work you're gonna do exactly what we're doing with CRISPR rather than being super precise we've sort of going in with a hammer and smashing the gene and then seeing what happens it's like if you kind of wanted to understand how a car worked so you opened up the you know opened up the hood and just started smashing pieces and then found the way in which the car stopped working so like you know if the car just completely stops then maybe that doesn't tell you anything but if the car still works except the radiator is now broken then you understand that the bit that you smashed has something to do with the radiator and so that's the version of this that we're doing kind of very broad strokes just kind of breaking bits and seeing what breaks the next step is we take those eggs down to the lab to inject them with CRISPR and by we I mean me I'm going to do it all right y'all tone drew okay okay great here we have a gun free dairy egg from the top you move the needle back you approach Genki you get in and you present the payroll there is I did I owe you see look you can see the little red bursts inside CRISPR the eggs will develop and hatch like usual only the DNA inside has been altered by the CRISPR that we injected the caterpillars look well like normal caterpillars you'd never know the difference you look inside their bodies okay let's talk metamorphosis you've maybe heard that when a caterpillar morphs into its final form inside the chrysalis it completely liquefies into soup and that the liquid rearranges to form a butterfly this misconception has been repeated so often that it's replaced the truth and what actually happens is way cooler caterpillars mature from the inside out the larvae move through stages of growth called instars and when an in star gets big enough it crawls out of its skin and the next stage of growth emerges from the inside and when the caterpillar is just about big enough to form a chrysalis it already has some pieces of the adult butterfly inside of it what you're about to see absolutely blew my mind you see this and you're thinking no way no way these things as wings it's a robot it's not flying what the heck so I'm gonna make an incision between the two nostrils so two diaphragms check that out man this is incredible that is that's a larval wing that's a baby wing here we go you can see the veins and everything looks like a tiny we're flying Wow now this is the stage where not only the shape of the wings defined but our social position of patterns that's right caterpillars have baby butterfly wings inside them and even at this early stage the butterfly's wing pattern is being painted the team can label which genetic instructions are turned on in that baby wing and what's crazy is where we see certain genes turned on lines up perfectly with where the patterns will be on the adult butterfly and when CRISPR messes up that DNA instruction we can also see how the pattern is disrupted so the different genes that you study here in the lab lay down different parts of this pattern exactly so during all our development you have like a canvas of service but all communicating and the wings needs to decide where to make may be reflective scales all dark scales and it's really a little bit if I can make an analogy or sketch process where the outlines of each patterns all determine superiority is during metamorphosis and pupae chrysalis that really the scares of emerging and really the corals happens it's like a paint-by-numbers the genes they've identified draw in the boundaries and sort of say paint here later on inside the chrysalis different genes paint in the colors based on those early instructions the basic shapes the organization the consumption trains stripes the position of all the systems is that we super are in the Rafah which isn't i growing so now you know that caterpillars don't turn into total mush as they mature and they have some of the body parts hidden inside them but there is still a ton we don't know about how wings form inside the chrysalis if only we could see inside well some scientists have figured out a way to do that like our old friend Aaron Pomerance a PhD candidate at UC Berkeley what my lab tries to understand is the process of how butterflies form their wings and their scales which occurs in the pupil stage if you've ever stared at a pupa for long enough you may have been a little bit underwhelmed it doesn't look like they're doing a whole lot they don't really move they don't often look that flashy but just below the surface there's an incredible amount of change happening caterpillars actually do contain the precursors to their adult wings a small cluster of cells known as an imaginal disc and these cells have all the information necessary to transform into an adult wing when the time is right a couple of scientists Julian Kimura and Ryan all figured out on accident that if you removed this imaginal disc then now you would have a window into the pupa so now we can set up a time-lapse under a microscope to watch this entire process happen and what we see is incredible the cells and the immature wings start to specialize or differentiate into elaborate shapes and colors those gene instructions laid down in the baby butterfly wing tucked inside the caterpillar tell the wing where to paint in these colors it's both fascinating to me and important to science that we can watch the wings as they develop and see how colors are filled in the adult butterfly wing is covered in thousands and thousands of scales and this is where the color comes from because each one of those scales produces a specific color either through the architecture of the scale that creates a certain wavelength known as structural color or from pigments that become deposited inside those skills in these CRISPR mutants some of those cells are broken like the cars radiator so we can see how that changes the wing pattern when metamorphosis is complete the butterfly that emerges is called a mosaic mutant it has a change in some part of its body so here is the butterflies that we had in the cage over there a growl is where you have these lovely precisely placed silver spots all over the wing surfaces and then we knock out one gene at a gene called winte it literally just go in and smash it with a hammer so it's not there anymore and what we get is this so there are still silver spots but the arrangement of those silver spots is completely different in other butterfly species switching off that gene had totally different results it can make patterns fade or even disappear went a seems to be the master sketching pencil for butterfly wing patterns and they've identified another gene called optics that's more of the master paintbrush messing with it can turn some butterflies black and even make others iridescent blue these genes are part of the master set of instructions to build a body and we have similar genes in our bodies and we can't go in and break those genes in humans to understand how they work but we can learn something about them by decoding how these beautiful insect patterns are painted when people talk about CRISPR they like to think of creating mutant creatures or super humans but here in real life CRISPR has given scientists more power than ever to study how genetic instructions give us all of life's diversity of shapes and forms CRISPR has made this kind of gene tweaking cheaper faster and more accurate than ever this really makes me wonder if you have this ability to tweak how butterfly patterns end up coming out can we get more control one day and actually design butterfly artwork of our own make a butterfly look the way that we want them to I think we would be able to so we yes we can but Chuey and so you power it's you know it's so your tool that we have some also helmets nature so we are responsible to do things that all right to be ethical relative thank you to the great courses plus for supporting PBS Digital Studios the great courses plus is a digital learning service that allows you to learn about a range of topics from educators including Ivy League professors and from other experts from around the world you can go to the great courses plus.com slash ok to get access to a library of different video lectures about science math history literature or even how to cook play chess so become a photographer new subjects lectures and professors are added every month you can learn more by clicking on the link below or going to the great courses plus comm slash ok [Laughter] you [Music]

Channel: It's Okay To Be Smart

Views: 186,679

Rating: 4.9529772 out of 5

Keywords: science, joe hanson, it's okay to be smart, its okay to be smart, it's ok to be smart, its ok to be smart, public broadcasting service, nature, documentary, biology, evolution, butterfly, crispr, crispr cas9, butterflies, insects, genetics, genetic engineering, arnaud martin, dna, pbs, cas9, genome editing

Id: qjRQIoHUWtY

Length: 12min 11sec (731 seconds)

Published: Tue Jun 18 2019