They say that there is a strong city, its army is bold, which calls for intelligence and wisdom in every attack its city is exposed to, and quickly turns defeat into victory, not victory, for it forces his enemy to change tactics of war, so the more the enemy will develop his abilities and come back again with his weapons, he started City Army to recognize these weapons, study them well, and then summon the soldiers with cons -arms. It’s a strong army, isn’t it?
You might be curious about this city and this mighty army. Well, this city is your body, my friend, its army is the immune system, and the weapons are the antibodies your immune system makes to defend you. You have no doubt realized who the enemy is, yes, it is the foreign objects invading your body.
Even today, the human immune system is still very complex, and scientists and researchers go to great lengths to simultaneously decipher its complex and brilliant codes. And the immune system is not limited to humans – as some think – if I told you animals have it, you probably wouldn’t be surprised, in the end animals are mammals, and it wouldn’t be. strange. But you might be surprised when I speak to you at the microscopic level.Can you imagine that a small organism that cannot be seen with the naked eye has immune responses, like the ones your immune system triggers?إقرأ أيضا:صيغة استئناف قضية عمالية
Perhaps these immune responses to these microorganisms won’t be as sophisticated as those of humans, but what makes them sit on the Nobel table in 2020 calls for attention and careful study. By the way, this microorganism is a bacterium.
1987 Japanese scientist Yoshi Zumi Ishino and his research team observed during the analysis of the gene responsible for the production of the enzyme alkaline phosphatase in the bacterium Escherichia coli.Coli“They clone different sequences from repeated sequences For bacteria, It was interspersed with strange pauses. It was a mystery to them at the time, possibly due to the lack of capacity or the lack of sufficient DNA sequence data.
In 1993, a research team in the Netherlands discovered the existence of different strains of mutagenic tuberculosis bacteria.Mycobacterium tuberculosisIt has spaced sequences that are different from bacterial DNA repeats, as noted by Yoshi Zumi Ishino and her team. Based on the sequences of these spacers, the Dutch team divided the strains of TB bacteria using what is called profiling.إقرأ أيضا:Débarrassez-vous des applications malveillantes si elles sont sur votre téléphone!
Over time, these sequences have been observed in many types of bacteria and archaea. Researchers Francisco Mojica and Rod Janssen called them CRISPR, short for Clustered Regularly Interspaced Short Palindromic Repeats, which means short repeats of evenly spaced symmetrical clusters.
Genes and humans … a revolutionary journey that is not without risks
CRISPR – Cas9 systems as an acquired immune response
When CRISPR systems were first discovered, scientists believed it was a new DNA repair mechanism in ancient, thermophilic, true bacteria. And at the start of the 21st century, CRISPR came to light, and many researchers were interested in studying this technique, and my research team noticed that the spacer sequences are similar to those found in bacteria, viruses and plasmids. It does prove that these organisms were passing inside bacteria at one point, right?
Well, it’s true, these organisms have already passed inside bacteria and left their mark, and bacteria use this enemy attack in their defense because scientists have found that viruses cannot attack bacteria. containing strings of spacers. This leads us to wonder about the secret of this force acquired by bacteria. Maybe the secret lies in the breaks, we’ll see now.إقرأ أيضا:Download the best formula for a primary home ownership contract 2020
Imagine a quarrel with me that takes place between two organisms, one of them is virus and the other is prokaryotic organism such as bacteria, suppose the evil party is a virus, which attacks bacteria which do not cause no harm. The virus begins to use its first weapons of attack, which inject its DNA inside bacteria, in order to multiply and increase the number of its DNA inside, which in turn can cause death bacterial cells.
so what? Will the bacteria stand idly by? Of course not, the bacteria will show their resistance and start to use defense mechanisms, as they quickly release enzymes to collect parts of the DNA of the virus, and store its codes in the CRISPR region by adding and removing ( cut and paste) parts of the separating DNA in the CRISPR region.
When bacteria are subsequently exposed to a similar virus, bacteria can kill it more quickly, using the CRISPR Cas9 system, as in the following steps:
- Bacteria copy the DNA stored in the CRISPR region which takes the form of RNA, called rRNA.
- The rRNA was added to the enzyme Cas9 (cas9) specialized in cutting.
- When the enzyme and rRNA find the virus inside the bacterial cell, they search for the complementary region between the virus’s DNA and the rRNA.
- Once the complementary region is found, the DNA strands of the virus are released, at the same time the Cas9 enzyme lurks, waiting for the opportunity to separate the chains from each other and cut them at specific areas, causing perish the virus.
There are differences between viruses and on the basis of which viruses are classified, among which is the type of DNA, there are some viruses that have DNA and those that have RNA, and therefore, it is not It is not only case9 who is responsible for cutting the DNA of viruses, but it is a specialist. For DNA, while another type is cas13, which is an RNA specialist.
Some may have questions such as; What if the cas9 enzyme spoils and cuts regions of CRISPR instead of virus DNA sequences? Well, there are just components like: PAMs do directory work; In other words, its presence confirms to the cas9 enzyme that this DNA is specific for viruses and not for CRISPR regions, and thus cas9 avoids this mixing which can kill bacteria.
Is the Corona virus a form of biological weapon used in a war that claims to be pandemic?
CRISPR as a gene editing tool
Scientists began to straighten their research towards CRISPR-Cas9, seeking to exploit this copy-paste property, and many were eagerly awaiting the release. Genome By changing the sequences, thereby changing the genetic code, and then controlling gene expression, you can introduce new parts into DNA and trick normal cell processes. It’s similar to the juice making process, where you can change the flavor to your liking while the rest of the ingredients and the steps are fixed, just a simple change resulting in a completely different product.
In 2012, research was published indicating that the nucleotide sequences of rRNA that bind to its complementary target DNA sequences can be modified and that the Cas9 enzyme can be directed to cut any region of the rRNA. ‘DNA. In 2020, French scientist Emmanuel Charpentier and American Jennifer Doudna won the Nobel Prize in chemistry, in recognition of their efforts to develop CRISPR technology. Emmanuel discovered tracrRNA, which bacteria use to protect themselves against viruses, and then partnered with Jennifer to develop the technology, and it did.
The genome is between editing and sabotage
After humans turned to CRISPR, their ambition exploded because it was the best gene editing tool ever. And it began to be applied in food industries such as yogurt industry, because it is used to protect the nutrient medium from microorganisms used in these manufacturing processes against viruses, and CRISPR has also been used in agriculture to improve the strains of agricultural crops.
Dr Neville Sanjana of the New York City Genomics Center says:
“I think the public perception of CRISPR centers around the idea of using genetic modification in the clinic to treat disease.”
Some scientists used CRISPR technology to modify certain human genes in an experimental environment using laboratory animals, and the result was effective, which encouraged them to state that this technology would be very useful in correcting the flaws. genetics. And the treatment of certain diseases such as: cystic fibrosis, cataracts and anemia. It is expected that CRISPR will also be used to modify certain traits in humans, so that these traits are passed on to future generations.
The limitations of CRISPR lie in the possibility that it will fail, as it can have a success rate of up to 80%, but we cannot condone the potential damage it has, which can cause the introduction of unwanted mutations. In addition, its use in embryos raises many ethical concerns. And when you get these unwanted mutations or problems, the result is not genome modification, but genome destruction.
Attention does not mean prohibition
These risks have prompted many people not to accept this technology, due to the many questions that were spinning in their minds about it, especially when it is used to control germline modification, so do we have the right? to introduce genetic modifications into the human body? Should we make changes that could affect future generations without their consent? Many questions arose in this regard, until the National Academies of Medicine and Engineering released a report stating that such genetic changes would only be made on dangerous diseases, and they stressed that caution does not mean not the ban.
2020 Nobel Prize in chemistry to develop precision gene editing