The CRISPR-Cas9 system is a tool for cutting DNA at a specifically targeted location. The technique has already revolutionized gene editing but scientists are always looking for new possibilities, so what else can CRISPR do? Since being discovered in a bacterial immune system CRISPR-Cas9 has been adapted into a powerful tool for genomic research. There are two components to the system: a DNA-cutting protein called Cas9 and an RNA molecule known as the guide RNA. Bound together, they form a complex that can identify and cut specific sections of DNA. First, Cas9 has to locate and bind to a common sequence in the genome called a PAM. Once the PAM is bound, the guide RNA unwinds part of the double helix. The RNA strand is designed to match and bind a particular sequence in the DNA. Once it’s found the correct sequence, Cas9 can cut the DNA – its two nuclease domains each make a nick leading to a double strand break. Although the cell will try to repair this break, the fixing process is error-prone and often inadvertently introduces mutations that disable the gene. This makes CRISPR a great tool for knocking out specific genes. But making double strand breaks isn’t all CRISPR can do. Some researchers are deactivating one or both of Cas9’s cutting domains and fusing new enzymes onto the protein. Cas9 can then be used to transport those enzymes to a specific DNA sequence. In one example, Cas9 is fused to an enzyme, a deaminase, which mutates specific DNA bases – eventually replacing cytidine with thymidine. This kind of precise gene editing means you could turn a disease-causing mutation into a healthy version of the gene or introduce a stop codon at a specific place. But it’s not all about gene editing. Several labs have been working on ways to use CRISPR to promote gene transcription. They do this by deactivating Cas9 completely so it can no longer cut DNA. Instead, transcriptional activators are added to the Cas9 by either fusing them directly or via a string of peptides. Alternatively, the activators can be recruited to the guide RNA instead. These activators recruit the cell’s transcription machinery, bringing RNA polymerase and other factors to the target and increasing transcription of that gene. The same principle applies to gene silencing. A KRAB domain fused to the Cas9 inactivates transcription by recruiting more factors that physically block the gene. A more outside-the-box idea for using CRISPR is to attach fluorescent proteins to the complex so you can see where particular DNA sequences are found in the cell. This could be useful for things like visualizing the 3D architecture of the genome, or to paint an entire chromosome and follow its position in the nucleus. CRISPR has already changed the face of research but these new ideas show that what’s been achieved so far could just be the tip of the iceberg when it comes to CRISPR’s potential. Whatever comes next, it seems the CRISPR revolution is far from over.

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100 thoughts on “CRISPR: Gene editing and beyond”

  1. So our target sequence must be close to PAM? polymerase only error-prone 1 in 3000 bases maybe for such short sequences it pretty much does the job without errors? therefore no knockout and do we know exactly which nucleotide would it nick?

  2. https://www.google.ca/search?q=fluorescent+human+chromosome&source=lnms&tbm=isch&sa=X&ved=0ahUKEwjn747Z0uzcAhXrmOAKHdD5BXEQ_AUICigB&biw=1440&bih=828#imgdii=DKs3_lUjt9bYoM:&imgrc=6RGXc-Ph4ft9eM:

  3. f… you fucking idiots with your fucking explorations! Only one can control what it is to control and control it because it has created it! you f…..g people will fuck all up and burn the race for a little green paper for you to buy a good car! f… you and I hope that you will break apart before you do something else to destroy balance!

  4. The truth about Crispr: https://www.naturalnews.com/2017-02-19-alert-dangerous-new-type-of-gmo-being-unleashed-into-food-supply.html

  5. im in the last year of high school and need to make a big project/paper about anything of my choice. i choosed CRISPR-Cas9 because it seems very interesting! maybe somebody has some tips that i can use when making my project/paper? amazing video btw much love from the netherlands

  6. But what is it?? Yes, I know it is a gene editing technique. But what IS it? Like, what does it LOOK like???? What is the physical form of it? ??? what are the mechanics of it?? And why in hell can I never find a good answer for this question? Has no one ever thought of this before??? Geez people.

  7. Crispr seems fascinating. But what about the facts surrounding the theories of nature vs nurture. Genes may not always be expressed depending on one’s environment. Or genes can be turned off by one’s environment. There are other things that can go wrong like completely and entirely new diseases or new damage brought on by this DNA editing. It seems like a brilliant idea but where are we drawing the line with ethics…

  8. When this is done to one cell? Does the body somehow copy it to the others and spreads it through out the body to fix them all?

  9. ¿ CAN WE MAKE TELOMERES GROW WITH C.R.I.S.P.R. CAS-9 ?

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  10. I've not seen yet even one supposed 'explanation' of how CRISPR works …that really works. All are jumbled, vague 'pretty-pictured' overviews that, apart from emphasizing how 'cool' all this is along with some muddled metaphors and graphics, fail entirely in their stated task. Please, someone with some real educative credentials and flair, please give this a shot.

  11. How does this gene editing method affects off springs ? Can there be any potential negative side effects like unwanted mutations ?

  12. What year they going to start using crisper cast nine to help people get rid of cancer HIV leukemia all timers can you give me a year Larry price at Larry price 1961 gmail.com I'll be waiting for your answer thank you very much bless you

  13. How can we be able to do these things and people still not understand what science is or even that it is a good thing….

  14. Amazing! Do you think by disabling the genes and introducing certain mutations could help the production of amyloid protein build up in the brain creating those amyloid plaques?

    Once amyloid-beta reaches the tipping point it kills the Neuron which becomes shrivelled up into a neurofibrillary tangle n Alzheimers patients right?

    My questions are:

    – How does introducing a new enzyme to a protein get to dictate where it goes in the specific genetic sequence?
    – How are they able to add a stop codon to certain parts of RNA?

    I love the idea of florescent proteins though, is it possible to be able to map certain genetic traits if we follow it clearly enough!!

  15. Hey Nature. where can I find some more info about the use of CRISPR-GFP chimeras for spatial detection of speecific sequences?

  16. Layman's question. I was born with a genetic flaw that has caused me problems now that I am almost 50 years old. Can CRISPR tech help me?

  17. WARNING: Law of Unexpected Consequences = enthusiastic naive scientists who only care about their personal careers & never think about the consequences that, being biological can explode across the planet irreversibility.

  18. Advanced medicine & education, new energies & materials, IoT & big data processing……the next generation techs will be centered on AI.

    They will remove the barrier between artifacts & natural objects, being friendly to natural ( including body-internal ) & social environments.

    I hope we can achieve the sustainability of civilization by new, epoch-making technologies & wise, humanistic policies 💖.

    https://ameblo.jp/lovelucifer/entry-12272343398.html / https://ameblo.jp/lovelucifer/entry-12429842470.html

  19. Found this because I was doing some research on Crispr. I am a cancer patient and wondering if cure is possible. I saw a video from a doctor and mentioned that Crispr is the future for cancer. Most cancer starts from gene mutation. If crispr can edit or cut those mutated genes… viola! Cancer free!!!! The future is near…

  20. So now will you believe that reptilians modified our DNA they deactivated 10 of the 12 strands. They are the royal bloodlines ancestors. right after they killed the dinosaurs, no it wasn't meteorites!

  21. My mind is blown by the animation😵😱 thank you so much for making this topic understandable and kudos for your hard work especially Mr. Eric Small and Mr. Elizabeth McDonald🙏🙌

  22. 80% of the worlds wild fires are burning in Africa; the lungs of the Earth are burning in the Amazon Basin.
    If academics like you don't get off your fat ass and lobby politicians all life on Earth will be extinct within 50 years.

  23. I love the background theme haha, also, thanks for this overview, great starting point to research CRISPR applications.

  24. I wish this technology was discovered several years ago and it's use was Standard practice in medicine. We've only just begun, and for those this technology could have helped has been a little to late. I hope this practice because as advances as the iPhone and we can save lives now and not later.

  25. Я подозреваю, что именно в скором времени будут говорить креационисты. 😉

  26. When humanity get to fully control this and manufacture massive scale nanotech that has the intelligence to bound to specific locations on the DNA we will surely declare our selfs immortals. This means unlimited DNA reparation that prevents aging from radical particles liberation from the metabolism fueling whit the oxigen truh the body. And of course can act as anybody and neutralize any kind of infectious desiese or repair genetical syndroms. This can also be the new "nuclear bomb extermination weapon" since it can be used to dmg the DNA and cause death in just a few hours. I think we may have access to this technology in less of a 1000 years. And our humanity will not be human anymore…

  27. This is a dangerous technology, just like the invention of atomic bomb. This can lead to large scale manipulation of the genome for ignoble purposes.

  28. My dream is to end infertility in a none distant future, and that anyone could have biological children. Doesnt matter the sex of the parents.

  29. New feature – "medicine" for your phone!

    Instructions for use video file in the description below!

    Until completely free!

    Helps against many antibiotic-resistant diseases.

    As a bonus, it is also the strongest painkiller!

    https://www.youtube.com/watch?time_continue=2&v=TTNdcgQjvfM

  30. CRISPR is cool. But task of cutting DNA & ligating our gene of interest was still possible using sequence specific restriction enzymes + lygase.

    So how CRISPR is advantageous ?

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