What I'm going to show you are the astonishing molecular machines that create the living fabric of your body. Now molecules are really, really tiny. And by tiny, I mean really. They're smaller than a wavelength of light, so we have no way to directly observe them. But through science, we do have a fairly good idea of what's going on down at the molecular scale. So what we can do is actually tell you about the molecules, but we don't really have a direct way of showing you the molecules.
Pokazaću vam zadivljujuće molekularne mašine koje stvaraju živu materiju vašeg tela. Molekuli su stvarno, stvarno malecki. A kada kažem mali, stvarno to mislim. Manji su od talasne dužine svetlosti, pa zato ne postoji način da ih direktno posmatramo. Ali zahvaljujući nauci, imamo prilično dobru predstavu šta se događa na nivou molekula. Zato zapravo možemo da vam pričamo o molekulima, ali nemamo neposredan način da vam pokažemo molekule.
One way around this is to draw pictures. And this idea is actually nothing new. Scientists have always created pictures as part of their thinking and discovery process. They draw pictures of what they're observing with their eyes, through technology like telescopes and microscopes, and also what they're thinking about in their minds. I picked two well-known examples, because they're very well-known for expressing science through art.
Jedan način da to prevaziđemo jeste slikanje. Ova ideja nije stvarno nova. Naučnici su oduvek slikali, to je deo razmišljanja i procesa pronalaženja. Slikaju ono što posmatraju očima, koristeći tehnologije kao što su teleskopi i mikroskopi, i takođe ono o čemu razmišljaju. Izabrao sam dva poznata primera, jer su poznata po prikazivanju nauke putem umetnosti.
And I start with Galileo, who used the world's first telescope to look at the Moon. And he transformed our understanding of the Moon. The perception in the 17th century was the Moon was a perfect heavenly sphere. But what Galileo saw was a rocky, barren world, which he expressed through his watercolor painting.
Počeću sa Galilejem, on je koristio prvi teleskop na svetu da posmatra Mesec. Transformisao je način na koji razmišljamo o Mesecu. U 17. veku se smatralo da je Mesec savršena nebeska sfera. Ali je Galilej video da je to stenovit, pust svet, koji je prikazao na svojim akvarelima.
Another scientist with very big ideas, the superstar of biology is Charles Darwin. And with this famous entry in his notebook, he begins in the top left-hand corner with, "I think," and then sketches out the first tree of life, which is his perception of how all the species, all living things on Earth are connected through evolutionary history -- the origin of species through natural selection and divergence from an ancestral population.
Još jedan naučnik sa velikim idejama, velika zvezda biologije, je Čarls Darvin. Čuveni prikaz u njegovoj svesci on započinje komentarom u gornjem levom uglu: ''Ja mislim,'' a onda skicira prvo drvo života, što je njegovo viđenje opšte povezanosti svih vrsta, svih živih stvari na Zemlji, evolucionom istorijom, to je nastanak vrsta putem prirodne selekcije i odvajanje od populacije predaka.
Even as a scientist, I used to go to lectures by molecular biologists and find them completely incomprehensible, with all the fancy technical language and jargon that they would use in describing their work, until I encountered the artworks of David Goodsell, who is a molecular biologist at the Scripps Institute. And his pictures -- everything's accurate and it's all to scale. And his work illuminated for me what the molecular world inside us is like.
Čak i kao naučnik, išao sam na predavanja molekularnih biologa i bila su mi potpuno nerazumljiva, zbog svih složenih tehničkih izraza i žargona koji koriste za opis svog rada, dok nisam naišao na umetničke radove Dejvida Gudsela, koji je molekularni biolog na Skrips institutu. Na njegovim slikama je sve tačno i proporcionalno. Njegov rad mi je pojasnio kako izgleda molekularni svet u nama.
So this is a transection through blood. In the top left-hand corner, you've got this yellow-green area. The yellow-green area is the fluid of blood, which is mostly water, but it's also antibodies, sugars, hormones, that kind of thing. And the red region is a slice into a red blood cell. And those red molecules are hemoglobin. They are actually red; that's what gives blood its color. And hemoglobin acts as a molecular sponge to soak up the oxygen in your lungs and then carry it to other parts of the body.
Ovo je presek kroz krv. U gornjem levom uglu vidite ovaj žuto zeleni deo. Žuto zeleni deo su tečnosti u krvi, koja se uglavnom sastoji iz vode, ali tu su i antitela, šećeri, hormoni, takve stvari. A crveni region je presek kroz crvena krvna zrnca. A ovi crveni molekuli su hemoglobini. Oni su stvarno crveni; to daje boju krvi. Hemoglobin deluje kao molekularni sunđer koji upija kiseonik u plućima i prenosi ga u druge delove tela.
I was very much inspired by this image many years ago, and I wondered whether we could use computer graphics to represent the molecular world. What would it look like? And that's how I really began. So let's begin.
Inspirisala me je ova slika pre mnogo godina, pa sam se pitao da li bismo mogli da koristimo kompjutersku grafiku da predstavimo svet molekula. Kako bi izgledao? Tako sam zapravo započeo. Hajde da počnemo.
This is DNA in its classic double helix form. And it's from X-ray crystallography, so it's an accurate model of DNA. If we unwind the double helix and unzip the two strands, you see these things that look like teeth. Those are the letters of genetic code, the 25,000 genes you've got written in your DNA. This is what they typically talk about -- the genetic code -- this is what they're talking about. But I want to talk about a different aspect of DNA science, and that is the physical nature of DNA. It's these two strands that run in opposite directions for reasons I can't go into right now. But they physically run in opposite directions, which creates a number of complications for your living cells, as you're about to see, most particularly when DNA is being copied.
Ovo je DNK u klasičnoj formi duplog heliksa. Ovo je snimak dobijen rendgenskom kristalografijom, to je precizan model DNK. Ako odmotamo dupli heliks i odvežemo dva lanca, vidite ove stvari što liče na zupce. To su slova genetskog koda, 25.000 gena koji su upisani u vašu DNK. O tome obično govore - o genetskom kodu - upravo na ovo misle. Ali želim da vam pričam o drugom aspektu nauke o DNK, a to je fizička priroda DNK. Ova dva lanca se pružaju u suprotnim smerovima iz razloga u koje sada neću ulaziti. Ali se fizički pružaju u suprotnim smerovima, što stvara brojne komplikacije za vaše žive ćelije, kao što ćete videti, a najviše kada se prepisuje DNK.
And so what I'm about to show you is an accurate representation of the actual DNA replication machine that's occurring right now inside your body, at least 2002 biology. So DNA's entering the production line from the left-hand side, and it hits this collection, these miniature biochemical machines, that are pulling apart the DNA strand and making an exact copy. So DNA comes in and hits this blue, doughnut-shaped structure and it's ripped apart into its two strands. One strand can be copied directly, and you can see these things spooling off to the bottom there. But things aren't so simple for the other strand because it must be copied backwards. So it's thrown out repeatedly in these loops and copied one section at a time, creating two new DNA molecules.
Ono što ću vam sada pokazati je tačan prikaz stvarne mašine za replikaciju DNK koja se sada odvija u vašem telu, barem prema biologiji iz 2002. Znači DNK ulazi u mašineriju za proizvodnju sa leve strane, i sudara se sa ovim skupom, ovim minijaturnim biohemijskim mašinama, koje rastavljaju DNK lance i prave tačnu kopiju. Dolazi DNK i udara u ovu plavu, okruglu strukturu sa rupom u sredini i razdvaja se na dva dela. Jedan lanac je moguće direktno prepisati, možete videti ove stvari koje se odmotavaju tamo na dnu. Ali stvari nisu toliko jednostavne za drugi lanac jer se mora prepisivati unazad. Pa se okreće nanovo u ovim petljama i prepisuje deo po deo, stvarajući dva nova DNK molekula.
Now you have billions of this machine right now working away inside you, copying your DNA with exquisite fidelity. It's an accurate representation, and it's pretty much at the correct speed for what is occurring inside you. I've left out error correction and a bunch of other things.
Imate milijarde ovih mašina koje u ovom trenutku rade u vama, koje prepisuju vašu DNK sa izuzetnom preciznošću. To je tačan prikaz, i prilično tačna brzina za ono što se događa u vama. Izostavio sam ispravljanje grešaka i mnogo drugih stvari.
(Laughter)
This was work from a number of years ago-- Thank you.
Ovo je urađeno pre nekoliko godina. Hvala.
(Applause)
(Aplauz)
This is work from a number of years ago, but what I'll show you next is updated science, it's updated technology. So again, we begin with DNA. And it's jiggling and wiggling there because of the surrounding soup of molecules, which I've stripped away so you can see something. DNA is about two nanometers across, which is really quite tiny. But in each one of your cells, each strand of DNA is about 30 to 40 million nanometers long. So to keep the DNA organized and regulate access to the genetic code, it's wrapped around these purple proteins -- or I've labeled them purple here. It's packaged up and bundled up. All this field of view is a single strand of DNA. This huge package of DNA is called a chromosome. And we'll come back to chromosomes in a minute.
Ovo je urađeno pre nekoliko godina, ali ono što ću vam pokazati sledeće je nova nauka, usavršena tehnologija. Ponovo, počinjemo sa DNK. Ona se tu mrda i drma zbog okolne supe od molekula, koju sam sklonio kako biste mogli nešto da vidite. DNK ima oko dva nanometra u prečniku, što je stvarno veoma malo. Ali u svakoj vašoj ćeliji, svaki lanac DNK je dug oko 30 do 40 miliona nanometara. Da bi DNK bila organizovana i da bi pristup genetskom kodu bio regulisan, obmotana je oko ovih ljubičastih proteina - ili sam ih ovde obeležio ljubičastom bojom. Zapakovana je i sva je na gomili. Sve ovo što se vidi je jedan jedini lanac DNK. Ovo ogromno pakovanje DNK se zove hromozom. Vratićemo se ubrzo na hromozome.
We're pulling out, we're zooming out, out through a nuclear pore, which is the gateway to this compartment that holds all the DNA, called the nucleus. All of this field of view is about a semester's worth of biology, and I've got seven minutes, So we're not going to be able to do that today? No, I'm being told, "No."
Približavamo se, udaljavamo se, kroz nuklearnu poru, koja čini prolaz u deo koji sadrži svu DNK koji se naziva jedro. Sve što se vidi ovde se predaje ceo jedan semestar na biologiji, a ja imam sedam minuta. Znači to nećemo moći danas da stignemo? Kažu mi: ''Ne.''
This is the way a living cell looks down a light microscope. And it's been filmed under time-lapse, which is why you can see it moving. The nuclear envelope breaks down. These sausage-shaped things are the chromosomes, and we'll focus on them. They go through this very striking motion that is focused on these little red spots. When the cell feels it's ready to go, it rips apart the chromosome. One set of DNA goes to one side, the other side gets the other set of DNA -- identical copies of DNA. And then the cell splits down the middle. And again, you have billions of cells undergoing this process right now inside of you.
Ovako izgleda živa ćelija posmatrana kroz svetlosni mikroskop. Snimana je u toku dugog perioda vremena, zato možete da vidite da se kreće. Omotač jezgra se razgrađuje. Ove stvari u obliku kobasica su hromozomi i fokusiraćemo se na njih. Oni se kreću na ovaj zanimljiv način, a fokusirani su na ove male crvene tačke. Kada ćelija oseti da je spremna, dolazi do razdvajanja hromozoma. Jedan komplet DNK odlazi na jednu stranu, a druga strana dobija drugi komplet DNK - identične kopije DNK. A onda se ćelija deli po sredini I opet, imate milijarde ćelija koje prolaze kroz ovaj proces upravo sada u vama.
Now we're going to rewind and just focus on the chromosomes, and look at its structure and describe it. So again, here we are at that equator moment. The chromosomes line up. And if we isolate just one chromosome, we're going to pull it out and have a look at its structure. So this is one of the biggest molecular structures that you have, at least as far as we've discovered so far inside of us. So this is a single chromosome. And you have two strands of DNA in each chromosome. One is bundled up into one sausage. The other strand is bundled up into the other sausage.
Sada ćemo se vratiti nazad i fokusirati se na hromozome i pogledati i opisati njihovu strukturu. Opet smo ovde na tom ekvatorskom polu ćelije. Hromozomi se poređaju. Izolovaćemo samo jedan hromozom, izvućićemo ga i pogledati njegovu strukturu. Ovo je jedna od najvećih molekulskih struktura koje imate, barem na osnovu onoga što do sada znamo o nama. Znači ovo je jedan hromozom. Imate dva lanca DNK u svakom hromozomu. Jedan je skupljen u jednu kobasicu. Drugi lanac je skupljen u drugu kobasicu.
These things that look like whiskers that are sticking out from either side are the dynamic scaffolding of the cell. They're called microtubules, that name's not important. But we're going to focus on the region labeled red here -- and it's the interface between the dynamic scaffolding and the chromosomes. It is obviously central to the movement of the chromosomes. We have no idea, really, as to how it's achieving that movement.
Ove stvari koje izgledaju kao brkovi koji štrče sa obe strane su dinamične skele ćelije. Zovu se mikrotubule. To ime nije važno. Ali ćemo se fokusirati na ovaj crveni region, obeležio sam ga crvenom bojom, i to je dodirna površina između dinamičnih skela i hromozoma. Očigledno je ključno za kretanje hromozoma. Nemamo predstavu kako se zapravo postiže to kretanje.
We've been studying this thing they call the kinetochore for over a hundred years with intense study, and we're still just beginning to discover what it's about. It is made up of about 200 different types of proteins, thousands of proteins in total. It is a signal broadcasting system. It broadcasts through chemical signals, telling the rest of the cell when it's ready, when it feels that everything is aligned and ready to go for the separation of the chromosomes. It is able to couple onto the growing and shrinking microtubules.
Proučavali smo ovo što se naziva kinetohor, preko sto godina intenzivnog proučavanja, i tek sada počinjemo da otkrivamo o čemu se radi. Sastoji se od oko 200 različitih vrsta proteina, hiljada proteina ukupno. To je sistem za emitovanje signala. Emituje hemijske signale, govori ostatku ćelije kada je spreman, kada smatra da je sve poređano i spremno za razdvajanje hromozoma. U stanju je da se spoji sa mikrotubulama koje rastu i smanjuju se.
It's involved with the growing of the microtubules, and it's able to transiently couple onto them. It's also an attention-sensing system. It's able to feel when the cell is ready, when the chromosome is correctly positioned. It's turning green here because it feels that everything is just right. And you'll see, there's this one little last bit that's still remaining red. And it's walked away down the microtubules. That is the signal broadcasting system sending out the stop signal. And it's walked away -- I mean, it's that mechanical. It's molecular clockwork.
Uključen je u rast mikrotubula, i u stanju je privremeno da se spoji sa njima. Takođe je to sistem za skretanje pažnje. U stanju je da oseti kada je ćelija spremna, kada je hromozom na pravom položaju. Ovde postaje zelen jer smatra da je sve baš kako treba. Videćete, ima jedan poslednji mali deo koji je još crven. I prelazi nadole niz mikrotubule. To je stop signal koji šalje sistem za emitovanje. I otišao je. To je mehanički proces. To je molekularni časovnik.
This is how you work at the molecular scale. So with a little bit of molecular eye candy,
Tako funkionišete na molekularnom nivou. Sa malo molekularnog šareniša,
(Laughter)
imamo kinezine, ove narandžaste.
we've got kinesins, the orange ones. They're little molecular courier molecules walking one way. And here are the dynein, they're carrying that broadcasting system. And they've got their long legs so they can step around obstacles and so on. So again, this is all derived accurately from the science. The problem is we can't show it to you any other way.
To su mali molekularni kuriri koji idu u jednom pravcu. Ovo su dineini. Oni prenose taj sistem za emitovanje. Imaju duge noge pa mogu da pređu preko bilo koje prepreke i tako dalje. Opet ponavljam, sve ovo je precizan prikaz nauke. Problem je u tome što to ne možemo da vam pokažemo na bilo koji drugi način.
Exploring at the frontier of science, at the frontier of human understanding, is mind-blowing. Discovering this stuff is certainly a pleasurable incentive to work in science. But most medical researchers -- discovering the stuff is simply steps along the path to the big goals, which are to eradicate disease, to eliminate the suffering and the misery that disease causes and to lift people out of poverty.
Istraživanje na granicama nauke, na granici ljudskog shvatanja, je zapanjujuće. Pronalaženje ovih stvari je svakako prijatan podsticaj za rad u nauci. Ali većini medicinskih istraživača je otkrivanje fenomena samo korak na putu ka velikim ciljevima, kao što su iskorenjivanje bolesti, sprečavanje patnje i nesreće koju bolest izaziva i oslobađanje ljudi od siromaštva.
Thank you.
Hvala vam.
(Applause)
(Aplauz)