DNA Topology

[@dinornis]

Supercoiling is something I struggle to get my head around, so this was super helpful, thank you!

[@MITxBio]

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[@himanshuprasad4409]

Juji

[@himanshuprasad4409]

Chutchattam

[@himanshuprasad4409]

Hello sir

[@himanshuprasad4409]

Boorchatta

[@laeunlee2537]

7:27 *video suddenly became horror

[@nephartuzim8879]

@Crosby Isaac Shut the fuck up dumb fucking bots

[@swatimavinkurve2305]

understood the whole concept of DNA topology in 7 minutes of this video than 7 hours of lecture. SO HELPFUL! THANK YOUU

[@mohammedkarim8627]

why is it so hard for me to understand such logical problem ?

[@ibnabbas5957]

thank you so much!!! your explanation was clear and easy to understand. My professors terrible and vague explanations was making me anxious and stressed - again thanks!!!

[@MITxBio]

You're very welcome! Join our free-to-audit courses, too! bit.ly/700xBio

[@hiranshreebabaria]

the way u guys explained using tubes was really helpful for visualization thank you very much for the video

[@MITxBio]

Thanks! Try our 7.28.1x Molecular Biology course, too. Registration open now for a Nov. 6 start. bit.ly/2AC9zP7

[@dmadhav4867]

Is it available now ​@@MITxBio

[@sandhyatelluri2346]

this is the best explained video I have watched so far about DNA supercoiling . Thank you so much.

[@dr.angelbaez63]

Thank you, when I understood the importance of each topoisomerase, I understood the whole process.

[@himul9526]

You have no idea how much I'm thankful you.

[@MITxBio]

Glad it was helpful! Join our courses, too! bit.ly/700xBio

[@shamithagovind7491]

"Thanks for watching" haahaa. :P

[@isupportcharliehebdo-moham3081]

nobody in the world could explain dna supercoiling this better..thanks.

[@MITxBio]

Thanks! Try our 7.28.1x Molecular Biology course, too. Registration open now for a Nov. 6 start. bit.ly/2AC9zP7

[@charliebrett7510]

could you please explain the writhe thing again? What circular strand in the right direction, which colour are you on about?

[@internalmedicinedoctordoct5057]

Try this kzbin.info/www/bejne/l3WZaJqfa8eLrdU

[@user-ec6kt2fg7m]

One moment you're playing with threads the next you're learning topology of DNA with Knot theory. Every time now that I think of grandma knitting I think of knot theory.

[@foodnuts4101]

Thank you for the video 😭 I finally understood!

[@pollydowdlepolly]

Still a bit confused but definitely understand more than I did when I started!

[@321123Nelly]

Same

[@jaivenkats8985]

A single thanks is not enough. Lots of love ❤❤❤❤

[@erikvitalis3107]

i am still confused af :D

[@shiyaoli2370]

Makes the topic so clear to understand! Thanks

[@MITxBio]

Thanks! Join us in the course as well. bit.ly/MITx7281x

[@timur2247]

Thank you. This video helps me understand this section of genetics.

[@MITxBio]

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[@arnabdas5883]

I'm just hugely grateful to you for making it so clear,I just banged my brain over this uncleared concept.

[@chantalgillett7797]

Extremely well done video. Thanks for the clear explanations.

[@MITxBio]

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[@kalkidanberhanu7708]

Awesome demo! This really cleared things up for me :)

[@MITxBio]

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[@OyeAbdullah]

Exactly what I need thanks

[@MITxBio]

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[@unlimitedmoney6342]

superb for explaining a most difficult concept

[@MITxBio]

Thanks! Try our Intro. Bio. course, too! bit.ly/700xBio

[@DN-pp7ow]

thank-you for providing this easier version of DNA topology.

[@nileenakd9253]

Well explained, thanks

[@michaella5110]

This video was so helpful, thank you!

[@luizinxz98]

excelent video! thx for sharing!

[@BD-rj8wb]

thx for sharing! thx for sharing! thx for sharing! thx for sharing! thx for sharing! thx for sharing!

[@generator6946]

Fantastic! More puzzle pieces!

[@bhaktizanzrukiya]

Not gonna lie that was 7 hours of lecture in that 7 mins

[@jakobvanspronsen9138]

understood it by watchihg once, and my english is awefull. This video is excelent!

[@akankshyadash8269]

Great explaination

[@chandnisingh8707]

Thank you 🔥

[@MITxBio]

You're welcome 😊

[@saeedekaasi1022]

Thank you very much. It was really helpful.

[@kelleyforeman]

thank you for this excellent video!

[@akhilachandrans4244]

Really helpfull. Finaly I got it.Thank u for this one..

[@MITxBio]

Glad it helped! Join our free-to-audit courses, too! bit.ly/700xBio

[@pujeetjha8265]

so good!

[@user-ky1kf3hu3v]

Thanks!

[@reenamohanta2994]

Wow .....thanks for the demonstration ......... it cleared a lot of confusion .....🙂

[@ritikabounthiyal6427]

Thanks for the video...nice explanation

[@MITxBio]

Glad you liked it!

[@el1339]

Superb... Plz make more videos... It would be helpful

[@MITxBio]

Thanks! Also try our Intro Biology course! bit.ly/700xBio

[@mayankrajsuman1553]

wonderful video, it helped me a lot.

[@MITxBio]

Glad it helped!

[@sadiakhalid3109]

Thanks ma'am

[@akshayam9773]

Is the course ready to start? it would be best if it does starts

[@MITxBio]

Thanks for your interest. 7.28.1x Molecular Biology Part 1 starts next week. Registration open now for a Nov. 6 start. bit.ly/2AC9zP7

[@teegee11-58]

Super helpful!

[@asmita_1999]

Thank you for this video ❤️

[@drujjawalrathore]

Wow!that was just awesome

[@MITxBio]

Thank you for the feedback! Try our courses as well. bit.ly/2AC9zP7

[@BorisNVM]

very cool video

[@hussainal-daheri3134]

شكراً

[@noahgrasser2557]

great video thank you:)

[@MITxBio]

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[@biofisicoquimica6470]

May I use your video for teaching? I would need to add Spanish subtitles. Thanks!

[@MITxBio]

Sorry, we didn't see this post earlier. Yes, you can use the video for teaching. We can add Spanish subtitles if you can do the translation. Email [e-mail] if you are still interested.

[@neginjson3147]

It was really helpful thanks:-)

[@marco15x15]

I can't understand why in the overwound DNA the number of bp/turn decreases c.c I mean, when we use the ethidium bromide, the number of bp/turn increases and the Wr tends to become positive. Could someone explain me this? Thanks PS: The video is awesome

[@annahall8480]

When you add intercalators like ethidium bromide, the binding of the intercalator to the base pairs results in a local unwinding of the helix by about 26 degrees - a reduction in twist (and an increase in writhe). Picture it - as the strands uncoil from each other slightly, the twists in the strand get further apart, so there are more bp/turn. However, this is UNtwisting the DNA from its relaxed state. In overwound DNA, intercalators are not used to wind it up. More twists are added to the double helix. As the twists in the strand increase in frequency, the number of bp/turn gets smaller.

[@akshithany6845]

Very informative.. Thank you

[@MITxBio]

Glad it was helpful!

[@funkdefied1]

Incredible

[@agriculturalknowledge2490]

thanks

[@donger0]

thank .... you....

[@PlushieMistress]

Question : why would any organism use Type 2 topoisomerase when using type one twice yields the same result ? one consumes ATP and the other Doesn't

[@samiali-gn1go]

When you have cell replication, in prokaryotes, you get two dna strand which are circular and connected with each-other thus when you want to separate the two cell dna circles from each-other you have to use the type two to losen up one of the helixes and take those two blunt ends to the other side, and from there each cell in the cell replication get a dna strand each. Otherwise you would have two interlocked dna circles. Do you understand why now?

[@PlushieMistress]

Why can't i cross over the strand one at a time with type one instead of two at the same time with type two? It even said in the video at 4:39 that crossing over one by one yields the same result .

[@pushpankkatare4226]

type two topoisomerase in bacteria helps in decreasing the linking number by two(refer Lehninger), but for eukaryotes type II topoisomerases cannot underwind DNA (introduce negative supercoils), but they can relax both positive and negative supercoils, I think what is told in the video is a bit misleading

[@brishtibrishti9206]

helped a loooot..thnx

[@diegogranados2793]

I still don't get it but still great video!

[@kuldeeparya9392]

After watching 20s to 30s of videos on thia topic... Finally!!!! I found someone who just explained this with so much ease and a dumb like me understood this 🥲 Thankyou so much mam for this explanation....you have saved me from failing in exam... thankyou so much again 🥲🥺

[@MITxBio]

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[@chunglamyu882]

what happen if simply increase the length of both strand? will it result more turns and more supercoiling?

[@poorvivishwakarma7945]

It was awesome mam..

[@kiranjeetkaur3529]

Thank you so much... now, finally i am able to understand DNA topology.... Best video...great...

[@MITxBio]

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[@deliamariacoman214]

i still didnt get the idea of positive and negative

[@siddhanthravichandran3245]

Ok from what I understand, positive supercoiling is when u tighten the coils together such that there is more tension, so the double helix wraps around itself to relive this tension. helps. Negative supercoil is when u loosen the coil, but now that's it's loose it can wrap around another time, sort of like giving it extra space, I imagine this to be sort of like how earphones get coiled up in pockets, since they are in an unwound state, they are loose and can be pushed around easier causing coils. This can be thought of as a compensation mechanism, where the coil " tries " to become tighter. Hope this helps , although u probably already found ur answer by now lol

[@sccm100]

4:34 isn't the top and the bottom the same shit? what difference does it make which strand goes on top?

[@alminmekic4418]

This is a way for me thinking of the difference and if the coilong is negative or positive. Put your thumb up like you would do when you wanna say "good job" for instance, do this with both of your hands. Picture your thumbs being the "ends" of the figures in the video, or the curves furthest away from the crossing point- your right hand shows the right end/curve, and your left hand showing the left end/curve. Then put your hands close to your desk and "rotate" your wrist forward so that your thumbs hit the desk. Your right thumb (as the right end) will rotate in the same way (forward) as positive supercoils. Your left hand (as the left end) will rotate in the same way (forward but the opposite end) as a negative supercoil. Most people ar right handed, and so am I, so I associate right with positive and left with negative.

[@Jmjholden]

the direction of the helix changes RH to LH and their bookkeeping system labels those at +1 or -1. This is a net change of 2

[@jorgeocampo650]

goog video

[@Rajeshkumar-dd8zr]

♥️♥️♥️Very very thanks fr the vdo♥️♥️♥️♥️

[@bubble_gum1533]

How did the writhe number increased by 2 by type 2 topoisomerase???

[@sukanyaroyart]

Initially, the dna was negatively supercoiled with a LEFT handed turn. So by convention, W=-1. Topoisomerase 2 cut both strands and passed the dna through the gap thus created. Now the dna became positively supercoiled with one RIGHT handed turn. So W=+1. So from -1 to +1, the value of W increased by 2.

[@YuRiSunga]

Upload about the Central Dogma!

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[@vishwabarchha2375]

The course mentioned is not available currently, is the course going to happen again?

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The course registration is now open. Join us! bit.ly/2AC9zP7

[@pageread7135]

Big FaN Love from india Please make subtitles in hindi

[@magihiyoriyona_nanatsu5092]

Can you please add the French subtitles? it's hard to concentrate translating your words and trying to understand

[@workpual4251]

2:30 it's not underwound it wound more why you call it underwound?

[@prateekyadav9811]

Please tell me what you used for the DNA model?

[@MITxBio]

Lab tubing that we painted red and blue on the inside.

[@ayanmandal834]

Wow

[@Sol-zf9wc]

6:24

[@Jini1177]

Great video!!! I was just wondering how does negatively supercoil DNA store energy in it's coil?

[@footfault1941]

While this is intriguing, evolutionists would find their job, hypothesizing a theory, further complicated! Great!

[@YuRiSunga]

Add Filipino subtitles

[@AweZombE]

Wait guys what does this have to do with topology of the DNA

[@DudeWhoSaysDeez]

everything

[@vloggerno1391]

please upload translation

[@MITxBio]

If you know someone who can do the translation (and tell us what language), we are happy to upload additional transcripts.

[@francislemieux07]

but why does't dna get tangled into a mess of knotsssssss

[@sukanyaroyart]

That's the requirement, that's how tgey are packaged and chromosomes are formed.

[@gyanichele]

Because there are topoisomerase which relaxes the DNA

[@RoyMustang.]

❤❤❤

[@ouahibasabri183]

I don't understand scientific english very well any translation to french

[@MITxBio]

If you know someone who can do the translation, we are happy to post additional subtitles.

[@parthchauhan7287]

Hi what is RNA ? How many types of RNA? The structure of RNA what is Amino Acids ? The structure of Amino acids ? What is Genes ? what is Chromosome? can you share information of list of systems of the Human body ?

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[@saramadeleinezinniker38]

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[@boozscha99]

fml

[@wasek152]

talking like robots is not helpful. thanks

[@rajashrimazumdar8390]

The accent is so irritating.. Not clearly understand.. 👎👎👎

[@internalmedicinedoctordoct5057]

kzbin.info/www/bejne/l3WZaJqfa8eLrdU Try this to solve your problem. Give comment about the video