Christophe wrote:Paragraph 2: synthesize virus proteins yes but to and by human cells no? So there is indeed an interaction of RNA and HUMAN cells ... But that does not mean that the DNA of the cell is modified but there is all the same a modification somewhere ... It is " temporary "and on the" surface "according to general public infographics but you will certainly tell us more ... because these are not very precise terms ... Because nothing but the" temporary "gives rise to doubt!
yes, virus proteins are synthesized by the enzymatic machinery of human cells ...
I don't know how far your knowledge of molecular genetics goes but as a reminder (sorry if all this is obvious and known)
a) we are made essentially of proteins which perform a whole bunch of functions, they constitute our tissues, skin, muscle, organs, but also the enzymes which make everything turn by full of biochemical reactions.
b) these proteins are made up of strings of 20 different amino acids which cling to each other, there may be thousands of them in a single protein. It is analogous to the letters of the alphabet which combine to make words and sentences.
c) the structure of proteins is encoded in our DNA, with a "coding" somewhat analogous to the ASCII code for letters. DNA itself comprises a sequence of bases among 4 (denoted A, T, C, G), and a group of 3 bases (a “codon”) encodes an amino acid. The sequence of codons therefore encodes a protein. There are also sequences to mark the start and end of a sequence. The details are very complex because the information is not stored in a linear fashion, but in principle you have to "read" DNA like a magnetic tape to build proteins. This reading is done by an enzymatic machinery, whose structure is itself encoded in DNA (knowing how it all started is the modern version of the egg and the chicken, and in fact we don't know).
Note that the DNA is in the form of TWO mirror molecules coiled in a helix (the famous "double helix"), the bases naturally pair with each other because they have structures that fit together one inside the other: A with T, and C with G. One strand carries a sequence like AATCCGAC ... and the other strand the complementary sequence TTAGGCTG ... etc ... To duplicate the DNA, we separate the two strands and we reconstruct the complementary strand on each (again it is enzymes that do that).
d) the translation of DNA into proteins does not take place directly. You start to open both strands and copy another molecule, messenger RNA, which is a little different from DNA but looks a lot like, which makes a "photocopy" of part of the DNA. Like him it carries 4 bases, almost the same except that the base "T" (thymine) is replaced by another base a little different "U" (uracil). But U pairs with A and C always with G. The messenger RNA will "photocopy" part of the DNA in the form of a complementary sequence, and will then be transported into the cell where it will be read and converted into proteins. . This two-step system makes it possible to express only part of the DNA, in fact each cell has all the genetic heritage but only reads part of it: a liver cell does not manufacture the same proteins as an eye or skin cell.
we therefore have the sequence DNA -> mRNA -> protein.
What does the virus do? a virus just has DNA or RNA encapsulated in a few proteins (including the "spike" protein for SARS-cov2) that it injects into a cell to infect it. The virus does not have the machinery to read its DNA (or RNA) but it uses the enzymatic machinery of the host cell, which in good faith makes the proteins of the virus, believing it to make its own proteins. the virus will multiply unless the immune system can recognize it and neutralize it.
The RNA vaccine consists of inoculating part of the virus's RNA, which will infect the cell and make it produce one of the proteins of the virus, but not the complete virus. A priori the virus cannot multiply, but the immune system will react to the proteins produced and be able to recognize them if a real virus appears.
A priori, RNA cannot be transcribed into DNA, except that some viruses like HIV have a special enzyme (reverse transcriptase) which can do that and therefore it does not content itself with producing its proteins, but will insert itself into our DNA by transforming us into GMOs! once in the DNA it is very difficult to dislodge. The coronavirus doesn't do this a priori, but apparently there are a few mechanisms that could do this with other enzymes. The risk of inserting RNA into DNA is not totally zero ... but it can just as well be done with the virus as with the vaccine! except that the vaccine encodes only one protein and is not a priori a virus.
Crispr-cas9 is something else. Like I said it's a system made to tinker with DNA, cutting it in specific places. To recognize these places, we use precisely the strands of messenger RNA complementary to the DNA on which they will stick, which will position the enzyme that cuts the DNA strand at the precise place where there is this sequence. If we want to tinker with human DNA, we therefore use Crispr-cas9 with human RNA, not virus RNA. So the risk of the vaccine has nothing to do with the Crispr-Cas9 technique. Even if there is indeed a small risk of incorporation of foreign genes, knowing that a) our genome is full of viral DNA that we have incorporated during millions of years of evolution and that b) if it does not affect not germ cells, it will not pass to our offspring.
To pass for an idiot in the eyes of a fool is a gourmet pleasure. (Georges COURTELINE)
Mééé denies nui went to parties with 200 people and was not even sick moiiiiiii (Guignol des bois)
