Until recently, we lived under the impression that most, if not all, of the genetic information was encoded in the segments of DNA that encode proteins. Now we understand that the issue is much more complex."
A mathematical analysis of the human genome led researchers to the conclusion that what is known as "junk DNA" has a use despite everything.
The term junk DNA refers to segments of the genome that seem to have no specific use. However, the IBM team identified patterns or "motifs" that are identical to the segment that is considered junk and the segment of DNA that codes for proteins. The presence of such "motifs" in DNA may indicate that these segments of the genome play an important role.
The findings of the report were published in the journal of the National Academy of Sciences in the USA. However, these findings still need to be confirmed in laboratory experiments, say the scientists who participated in the project.
Dr. Andrew McCallion, from the Department of Genetic Medicine at the Johns Hopkins University School of Medicine in Baltimore, who was not involved in the study, told the BBC: "Until recently, we have lived under the impression that most, if not all, genetic information is coded. in the DNA segments that code for proteins. Now we understand that the issue is much more complex."
The lead researcher in the project, Isidore Rigotsos and his colleagues from the Thomas Watson Research Center used mathematical pattern discovery tools to try to find the patterns in the genome. The technique is often used to mine useful information from huge databases in the world of business and science.
The fattening challenge
They looked for the patterns among 6 billion letters in the non-coding regions of the human genome and looked for repeating sequences or "motifs".
"One of the things that emerges from the article is that the junk DNA may not be junk, but it still needs to be confirmed." Dr. Rigortsos said. Among the possible roles - the sequence of the transcript - the beginning of the process that leads to the translation of the genetic code into peptides or proteins, and communication between the cells.
Dr. Rigourtsos said that his team's proposal for the role of the junk DNA is: "a connection between extensive areas of the genome that we didn't think had a role at all, with the part of the genome that we know the role of." said.
According to him, an average laboratory does not have the resources to confirm or refute this claim, so many resources are needed in the hands of many people." explained.
Genome silencing
The authors of the PNAS paper also say that the exact location of the beneficiaries is linked to small RNA molecules involved in the process, known as gene transcription silencers after the fact
Post-transcriptional gene silencing (PTGS). "A human embryo begins with the fertilized egg and divides into a wide variety of cells to become a human being" explains Dr. McCallion. "Each human cell contains the same complex of genes and what makes each cell different is the exact way in which the genes are turned on or off. The PTGS turns off the genes after the transcription process. One way is to do this through RNA interference ("RNA interference - involved in the production of double helix RNA molecules.
These molecules cause the depletion of another type of RNA molecules known as messenger RNA (mRNA), which regulate the gene. During transcription, the molecules are coded and carry information from the genes to the sites of protein synthesis. "It is possible that these areas are preparing structures that we have not seen so far," said Dr. Rigotsos.
If indeed one of them responds to an active ingredient involved in some process, this will expand the role of regulating cell development far beyond what we thought we had seen in the last decade."
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Thank you! In particular for the effort to formulate in non-scientific words.
Got it, I conclude:
The premRNA undergoes a process of removing introns. There are several options for what will be eliminated, and thus several types of mRNA are created.
When the Alu penetrates the premRNA there are two options: it only produces another type of mRNA and does not come at the expense of the existing ones (this is in case it is detected). Or he intervenes in the production of all that exists (because he is not identified).
privileged
Yes, it penetrates the DNA and it also binds to all RNAs. The point is that all RNA undergoes a process of cutting and splicing after transcription. The elements in DNA called "introns" are also copied into RNA but are later cut from it, so they are not part of the final product that will eventually be translated into a protein. Basically, the single gene in DNA is transcribed into one long piece of RNA from which many final RNA molecules (which are the ones that will eventually be translated into protein) can be formed. It all depends on what is cut out and what is left inside. So this sequence can enter the gene and be copied into RNA and then in some copies it will remain and in some it will be cut out. (ie remains both with the original protein and with a new mutant protein). But, if it enters the gene in a place that is not recognized later by the enzymes whose job it is to cut the RNA, then it will never be cut out and will always remain inside the protein. So the mutation will remain permanently without the original protein.
Hope it was clear and helped 🙂
http://www.ynet.co.il/articles/0,7340,L-3153994,00.html
miracles, or someone who understands biology,
a question -
ynet.co.il/articles/0,7340,L-3153994,00.html
In the link there is an article about junk DNA, about Alu, and I am copying:
"The problem only arises when a mutant Alu sequence undergoes permanent splicing, meaning it joins all the messenger RNA transcripts that are generated from the gene"
How can it be linked to some of the transcriptions and some not? If it penetrates the DNA - it penetrates any RNA that will be copied from it..?