The most transcendental process that occurs in all cells is protein synthesis, the investigation of the succession of amino acids that form the primary structure of the protein is included in the DNA. Through this post you will know everything about the basic structure of DNA.
DNA structure
In addition, known as deoxyribonucleic acid, it is a biopolymer whose monomers are nucleotides, this means that the structure of DNA is a polynucleotide, also, when asking How is DNA formed?, since it is a DNA molecule, it is normally made of two strands contracted one with respect to the other along a helical line, in most cases they call it "spiral twisted" and interrelated by hydrogen bonds.
The strands in the DNA molecule are ruled in opposite ways, the backbone of the DNA strands is made up of sugar phosphate moieties, and the nitrogenous bases of one strand are arranged in a strictly specific order opposite to the nitrogenous bases of the other. another complementary rule.
The DNA molecule has a very special place in the science of life, it is the DNA that stores complete information about the parts of DNA and the properties of the body and in all the smallest details, therefore, knowledge of all the structural features of DNA is fundamentally important.
It was with Watson and Crick's revelation in 1953 of the construction of the most significant DNA structure, the famous double helix, that a new era in the history of human advancement began, the era of molecular biology and genetics. biotechnology and molecular medicine established in molecular genetics.
It also has to do with the most fundamental aspects of DNA, especially those whose study is played out not only by biology and genetics, but also by chemistry, physics and mathematics, how the DNA structure and why this find is considered one of the largest in history and its relationship with the Science Characteristics, the asymmetry of all living beings in relation to the right and the left, on the central belief of molecular biology.
The universal law of living matter, about why DNAs are linear in some organisms and locked up in others, about mutations, damage to the DNA text, leading to numerous hereditary diseases, about the revolutionary DNA editing technology that is emerging before our eyes, which will allow in the near future to correct errors in the text of the patient's DNA.
To understand the biological function of DNA, you must first understand its molecular structure, this requires learning the vocabulary to talk about the building blocks of DNA and how these building blocks are assembled to form DNA molecules.
DNA function
DNA is the information molecule, it accumulates information to make other large molecules, called proteins, these illustrations are collected inside each of your cells, exchanged between 46 long structures known as chromosomes, these chromosomes are made up of thousands of more fragments short pieces of DNA, called genes, each gene puts together the knowledge to make pieces of proteins, whole proteins, or multiple specific proteins.
DNA is well suited to perform this biological function due to its molecular structure and the development of a series of high-throughput enzymes that are tuned to interact with this molecular structure in specific ways.
The coincidence between DNA structure and the activities of these enzymes is so effective and refined that DNA has become, over evolutionary time, the universal information-gathering molecule for all forms of life, nature has not yet found a better solution than DNA to store, express, and transfer instructions to make proteins.
How are the instructions written in DNA interpreted?
Human DNA contains billions of bases, and of these almost 99% are similar in all people, and it is similar to the way that the order of the letters of the alphabet can be used to form a word, the order of Nitrogen bases in a DNA sequence form genes, which in the language of the cell, tell cells how to make proteins, another type of nucleic acid, ribonucleic acid, or RNA, translates genetic information from DNA into proteins.
Nucleotides join together to form two long strands that spiral around to form an organization called a double helix. If you think of the double helix arrangement as a ladder, the phosphate and sugar molecules would be the sides, while the bases would be the rungs. , the bases of one strand are leveled with the bases of another strand, adenine pairs with thymine and guanine pairs with cytosine.
DNA molecules are long, so long, in fact, that they cannot fit into cells without the proper covering, to plug into cells, DNA folds neatly into chromosome structures, each chromosome has a single DNA molecule Humans have twenty-three pairs of chromosomes, which are located within the nucleus of the cell.
protein synthesis
Proteins are large molecules that can perform all kinds of tasks in cells, in turn they can facilitate chemical reactions such as Enzymes, they can also play a structural role such as Cytoskeletons, they can transmit signals to the cell surface, an example is membrane receptors and much more.
The genes written in our DNA are kind of recipes for making proteins, however, as the recipe is encoded in the form of nitrogenous bases (ATCG), it must first be translated, several proteins work in concert to achieve this, the chains of the DNA double helix must first be removed to give access to the target gene.
Then the proteins cause a mirror copy of the target DNA sequence as a kind of messenger RNA, this copy of the formula copied in the messenger RNA is forwarded out of the nucleus, because the proteins originate in other parts of the cell, there the ribosomes, small structures that predominate near the nucleus, will play with the cooks and read the recipe to make the protein.
The main components of proteins are amino acids and ribosomes use the messenger RNA model to couple the amino acids in the correct arrangement and form a long chain, amino acids are organic acid molecules developed by an amine, a chemical structure derived from ammonia .
Chemists know hundreds of them, but only twenty amino acids are used in proteins, but the protein in this linear representation is not yet complete, to be effective, it must fold back on itself like an origami, so it goes from one chain simple to a complicated three-dimensional structure.
the transcript
DNA has the basic illustrations to outline proteins through the decoding of the genetic code, this process is only viable thanks to two different phases, transcription and translation.
Transcription is the means by which DNA nucleotide strings are rewritten into additional RNA nucleotide strands, symbolizing that DNA molecules rewrite them into RNA molecules.
This operation is necessary so that the DNA alphabet is deciphered into something understandable for the entire apparatus that will have to carry out and put into practice the task foreseen by the genetic code, the information about the sequence of nucleotides that is going to be synthesized is copied into an RNA chain and then transported to the cytoplasm, the RNA synthesized is commonly called a transcript.
The translation process consists instead of interpreting the genetic information from the nucleotide sequence to the amino acid sequence, the translation takes place in ribosomes, structures composed of ribosomal RNA and proteins, which allow the assembly of amino acids from triplets of nucleotides.
Therefore, this is the phase where the genetic code is cracked, protein synthesis requires the simultaneous work of many ribosomes on a single messenger RNA molecule to simultaneously produce many copies of each individual protein.
T-RNA and r-RNA play an essential role in this process (transfer RNA and ribosomal RNA) since they allow the translation of the information carried by the messenger RNA, in a convenient and correct sequence of amino acids that will later form the proteins of our cells and therefore our body.
Translation and the genetic code
The first period of the gene term is «Transcription», which allows the information included in the DNA to be formulated in a copy of RNA, this messenger RNA communicates genetic information to the ribosomes where «Translation» takes part, the second step of the gene statement.
The base complementarity rule allows us to easily imagine the mechanism of transcription, during which information from DNA is transmitted to RNA, adenine versus uracil or thymine, cytosine versus guanine.
On the other hand, for translation, it is the nucleotide sequence of the messenger RNA that will determine the amino acid sequence of the protein, therefore, this passage from one "language" to another is a translation that obeys a code, the Code Genetic.
The genetic code is a sign that allows the transformation of a chain of nucleotides (DNA and RNA) into a chain of amino acids, the code involves the bases A, C, T and G, as well as the twenty amino acids, the genetic code has different traits:
- Codons represent nucleotide triplets and at the same time group an amino acid.
- The sequence of the gene and the sequence of the encoded protein are collinear, ie the length of the gene and the length of the primary structure of the final protein are proportional.
- The genetic code is universal, in fact, each amino acid has one or more codons and this at the level of a multitude of living prokaryotic and eukaryotic organisms.
- The genetic code is iterative, several codons are collected for the same amino acid, there are sixty-four codons and twenty amino acids, often the first two nucleotides of the codon require the amino acid, so the superfluity is due to the third nucleotide of the codon.
- The genetic code does not overlap, the nucleotides of a codon only participate in the code of a single amino acid, so the next amino acid will be encoded by the next codon present in the mRNA, we speak of the reading frame or reading frame.
- The code has a scoring system, the instruction codon is the AUG codon (GUG for my mitochondria) and the stop codons are the UAA (ochre), UAG (amber) and UGA (opal) codons, the UGA (opal ) is not present in mitochondria.
DNA and modern biotechnology
Biotechnology, as a science, was instituted at the end of the 70th century, at the beginning of the XNUMX's, it all started with genetic engineering, when Important scientists they managed to transfer genetic material from one organism to another without the execution of sexual techniques, for this, recombinant DNA or rDNA was used, this procedure is used to change or improve a specific organism.
Medical biotechnology includes production processes during which biological objects or medical substances are created, these are enzymes, vitamins, antibiotics, individual microbial polysaccharides that can be used as independent products or as auxiliary substances in the creation of various dosage forms, amino acids.
The discovery that genes are made of DNA and can be isolated, copied and manipulated has led to a new was of modern biotechnology, New Zealand has many applications for modern biotechnologies.
Humans have been manipulating living things for thousands of years, examples of early biotechnologies include domesticating plants and animals and then selectively breeding them for specific traits.
Modern biotechnologies involve the manufacture of useful products from whole organisms or parts of organisms, such as molecules, cells, tissues and organs, recent developments in biotechnology include genetically modified plants and animals, cell therapies and nanotechnology, these products are not used every day, but they can be beneficial for us in the future.
Biotechnology truly manifests itself with the genetic material of a cell. If we inspect a cell with a high-strength microscope, we would observe long thread-like distributions called chromosomes. These chromosomes, made up of DNA (deoxyribonucleic acid), are made up of devices called genes.
Genes control the production of particular proteins and proteins, in turn, determine the characteristics of an organism, in some cases a gene may govern a particular trait, such as an organism's resistance to disease, while in other cases , characteristics can be determined by many genes.
in animals
A skill called microinjection is the procedure often used to originate genetically modified or transgenic animals. Through this practice, a very fine needle is used to inject a solution of DNA molecules that have genes that carry the desired characteristics (such as resistance to diseases) in the Animal cell, usually in the embryonic period.
The genes are incorporated into the genetic material of animal cells, and the cells begin to express the characteristic determined by the new gene, the application of this microinjection technique could also have potential benefits for agriculture.
in bacteria
In certain bacteria, small natural circular segments of DNA called plasmids, which can be used for genetic engineering, DNA plasmid can be taken out of the bacterial cell, modified with the addition of a new gene, and put back into the cell.
With the new gene, the bacterial cell can now make the product of this gene as its own. Because bacteria transcribe very quickly, large volumes of bacteria possessing the reformed plasmid can be used to produce commercially significant quantities of a gene product. , such as a food additive or an animal vaccine, in short time steps.
in plants
Plant cells have tough outer walls, which makes gene delivery to plant cells a bit more challenging than is the case with bacteria, there are two main techniques by which this process is carried out.
