What is epigenetics? - Carlos Guerrero-Bosagna

Kako odluke koje donosite mogu uticati na vaše gene - Karlos Genero-Bosanja (Carlos Guerrero-Bosagna

Prevodilac: Ivana Krivokuća Lektor: Tijana Mihajlović

Here's a conundrum:

Evo zagonetke -

identical twins originate from the same DNA,

identični blizanci nastaju iz iste DNK,

so how can they turn out so different

pa kako onda ispadnu tako različiti,

even in traits that have a significant genetic component?

čak i u pogledu osobina koje imaju značajnu genetsku komponentu?

For instance, why might one twin get heart disease at 55,

Na primer, zašto jedna bliznakinja može dobiti srčano oboljenje u 55. godini,

while her sister runs marathons in perfect health?

dok njena sestra trči maraton savršenog zdravlja?

Urođeno naspram stečenog ima dosta veze sa time,

Nature versus nurture has a lot to do with it,

but a deeper related answer can be found within something called epigenetics.

ali se dublje povezani odgovori mogu naći u okviru nečeg pod imenom epigenetika.

That's the study of how DNA interacts

To je izučavanje načina na koji DNK ulazi u interakciju

with the multitude of smaller molecules found within cells,

sa mnoštvom manjih molekula pronađenih unutar ćelija

which can activate and deactivate genes.

koji mogu aktivirati i deaktivirati gene.

If you think of DNA as a recipe book,

Ako zamislite DNK kao knjigu sa receptima,

those molecules are largely what determine what gets cooked when.

ti molekuli većim delom određuju šta se i kada kuva.

They aren't making any conscious choices themselves,

Oni sami ne donose nikakve svesne odluke,

rather their presence and concentration within cells makes the difference.

već njihovo prisustvo i koncentracija unutar ćelija dovodi do promena.

So how does that work?

Kako to funkcioniše?

Do ekspresije gena u DNK dolazi kada se pročitaju i transkribuju u RNK,

Genes in DNA are expressed when they're read and transcribed into RNA,

which is translated into proteins by structures called ribosomes.

koju strukture zvane ribozomi prevode u proteine.

And proteins are much of what determines a cell's characteristics and function.

Proteini većim delom određuju karakteristike i funkciju ćelije.

Epigenetic changes can boost or interfere with the transcription of specific genes.

Epigenetske promene mogu da pojačaju ili ometaju transkripciju određenih gena.

The most common way interference happens is that DNA,

Najčešći način na koji se ometanje odvija

je da se DNK ili proteini oko kojih je obmotana,

or the proteins it's wrapped around,

gets labeled with small chemical tags.

obeleže malim hemijskim oznakama.

Skup svih hemijskih oznaka koje su vezane za genom date ćelije

The set of all of the chemical tags that are attached to the genome

of a given cell

is called the epigenome.

naziva se epigenom.

Some of these, like a methyl group, inhibit gene expression

Neki od njih, kao što je grupa metil, inhibiraju ekspresiju gena

by derailing the cellular transcription machinery

preusmeravanjem ćelijske aparature za transkripciju

or causing the DNA to coil more tightly,

ili dovodeći do toga da se DNK čvršće namotava,

čime je čine nepristupačnom.

making it inaccessible.

The gene is still there, but it's silent.

Gen je i dalje tamo, ali je neaktivan.

Boosting transcription is essentially the opposite.

Pojačavanje transkripcije je u suštini suprotno tome.

Some chemical tags will unwind the DNA, making it easier to transcribe,

Neke hemijske oznake će odmotati DNK, učiniti je lakšom za transkripciju,

which ramps up production of the associated protein.

što pojačava proizvodnju proteina sa kojim je u vezi.

Epigenetic changes can survive cell division,

Epigenetske promene mogu preživeti ćelijsku deobu,

which means they could affect an organism for its entire life.

što znači da mogu uticati na organizam čitavog njegovog života.

Sometimes that's a good thing.

Ponekad je to dobra stvar.

Epigenetic changes are part of normal development.

Epigenetske promene su deo normalnog razvoja.

The cells in an embryo start with one master genome.

Ćelije u embrionu započinju jednim glavnim genomom.

As the cells divide, some genes are activated

Dok se ćelije dele, neki geni se aktiviraju,

and others inhibited.

a drugi se inhibiraju.

Over time, through this epigenetic reprogramming,

Tokom vremena, kroz ovo epigenetičko reprogramiranje,

some cells develop into heart cells,

neke ćelije se razviju u ćelije srca,

and others into liver cells.

a druge u ćelije jetre.

Each of the approximately 200 cell types in your body

Svaka od otprilike 200 tipova ćelija u vašem telu

has essentially the same genome

ima u suštini isti genom,

ali sopstveni zaseban epigenom.

but its own distinct epigenome.

The epigenome also mediates a lifelong dialogue

Epigenom takođe posreduje u celoživotnom dijalogu

between genes and the environment.

između gena i sredine.

The chemical tags that turn genes on and off

Na hemijske oznake koje isključuju i uključuju gene

can be influenced by factors including diet,

mogu uticati faktori kao što su ishrana,

chemical exposure,

hemijsko izlaganje

and medication.

i lekovi.

The resulting epigenetic changes can eventually lead to disease,

Posledične epigenetske promene mogu na kraju dovesti do bolesti,

if, for example, they turn off a gene that makes a tumor-suppressing protein.

ako, na primer, isključe gen koji stvara protein za suzbijanje tumora.

Environmentally-induced epigenetic changes are part of the reason

Epigenetske promene koje proističu iz sredine predstavljaju deo razloga

why genetically identical twins can grow up to have very different lives.

zbog čega genetski identični blizanci mogu kao odrasli imati vrlo različite živote.

Kako blizanci postaju stariji, njihovi epigenomi se razilaze,

As twins get older, their epigenomes diverge,

affecting the way they age and their susceptibility to disease.

što utiče na način na koji stare i njihovu podložnost bolestima.

Even social experiences can cause epigenetic changes.

Čak i društvena iskustva mogu prorouzokovati epigenetske promene.

In one famous experiment,

U jednom poznatom eksperimentu,

when mother rats weren't attentive enough to their pups,

kada se majka pacov nije dovoljno starala o svojim mladuncima,

genes in the babies that helped them manage stress were methylated

geni kod beba koji su im pomagali da se izbore sa stresom bili su metilovani

i ugašeni.

and turned off.

To ne mora da prestane sa tom generacijom.

And it might not stop with that generation.

Most epigenetic marks are erased when egg and sperm cells are formed.

Većina epigenetičkih oznaka se briše kada se formiraju ćelije jajeta i sperme.

But now researchers think that some of those imprints survive,

Međutim, istraživači danas smatraju da neki od tih otisaka opstanu,

passing those epigenetic traits on to the next generation.

prenoseći te epigenetske osobine na sledeću generaciju.

Your mother's or your father's experiences as a child,

Iskustva vaše majke ili oca dok su bili deca

or choices as adults,

ili njihovi izbori u odraslom dobu

mogu oblikovati vaš epigenom.

could actually shape your own epigenome.

No, iako epigenetičke promene jesu lepljive,

But even though epigenetic changes are sticky,

they're not necessarily permanent.

nisu nužno i trajne.

A balanced lifestyle that includes a healthy diet,

Uravnoteženi životni stil koji podrazumeva zdravu ishranu,

exercise,

vežbanje

and avoiding exposure to contaminants

i izbegavanje izlaganja zagađivačima

may in the long run create a healthy epigenome.

mogu na duže staze stvoriti zdrav epigenom.

It's an exciting time to be studying this.

Uzbudljivo je vreme za izučavanje ovoga.

Scientists are just beginning to understand

Naučnici tek počinju da razumeju

how epigenetics could explain mechanisms of human development and aging,

kako epigenetika može objasniti mehanizme ljudskog razvoja i starenja,

as well as the origins of cancer,

kao i nastanak raka,

heart disease,

oboljenja srca,

mental illness,

mentalnih bolesti,

addiction,

bolesti zavisnosti,

and many other conditions.

kao i mnogih drugih stanja.

Meanwhile, new genome editing techniques are making it much easier

U međuvremenu, nove tehnike za izmenu genoma znatno olakšavaju

to identify which epigenetic changes really matter for health and disease.

utvrđivanje toga koje epigenetske promene zaista imaju značaj za zdravlje i bolesti.

Once we understand how our epigenome influences us,

Kada budemo razumeli kako naš epigenom utiče na nas,

we might be able to influence it, too.

možda ćemo moći i mi da utičemo na njega.