This article will talk about a vitally important phenomenon for all cells. In short, translation in biology is presented in the form of protein synthesis. Here we will consider its stages, their flow patterns and much more.
Acquaintance with the concept of translation in biology. What it is?
So. The processes of protein synthesis using amino acids, used as a building material, on matrices of information ribonucleic acids (mRNA, mRNA) are called translation in biology. This phenomenon occupies one of the key places in the development of all living organisms. Since proteins are the most important organic compounds among known lipids, carbohydrates, nucleic acids. The translation process is carried out with the participation of the ribosome, it occupies a major role in the synthesis.
The principle of the mechanism
What is biology translation? This is, first of all, the main process of cellular vital activity. To implement it, the cell requires the presence of non-membrane-type organelles called ribosomes. Ribosomes are called ribonucleoprotein structures consisting of small and large subunits, each one each. The ribosome recognizes codons consisting of three letters of mRNA. Next, there is a comparison with complementary anticodons of transport ribonucleic acid, which carries a number of amino acids and combines them with an increasing protein molecule, its chain. Moving along the messenger RNA, ribosomes are involved in protein synthesis, information about which is inherent in the messenger RNA itself.
Translation in biology is a vital process in which the recognition of cellular amino acids is carried out using “adapters”. They are transport-type RNA molecules. The process of combining amino acids with transport RNA is in the nature of an energy-dependent, enzymatic, aminoacyl-tRNA reaction.
Now, knowing where the translation occurs in biology, namely on the matrix, we consider this mechanism in eukaryotes and prokaryotes. It is important to know that this phenomenon is extremely different in these subdivisions. Many substances that inhibit translation in organisms of the prokaryotic type have a much weaker effect on the same process in multicellular organisms, which makes it possible to exploit them in the science of medicine. In the broadcast, the stages of initiation, elongation and termination are distinguished.
There is a concept of a reading frame. Its essence lies in the fact that the presence of three nucleotides in the codon creates the possibility of a different way of reading text of a genetic nature. There are three options for reading it, each of which begins with the 1st, 2nd or 3rd nucleotide. Most often, one frame is important, but there are interesting exceptions. It follows that the positioning of the ribosome at its initial stage will be very important.
Initiation process
Protein synthesis, most often, originates from AUG codons that are involved in the encoding of methionine. Such a codon is called an initiator. Translational initiation must be recognized by the ribosome and attract aminoacyl transport RNA. An important point in the initiation process is the presence of certain nucleotide sequences in the region of the initial codon. The presence of the initial AUG sequence is vital, since otherwise the synthesis would proceed in a chaotic manner.
Initiation cannot occur without the participation of initiation factors, specific protein molecules. The mechanisms of translational initiation in eu- and prokaryotes are also distinguished by the fact that the ribosomes of prokaryotic organisms can determine the location of the starting AUG and initiate initiation in any part of the messenger RNA. Eukaryotic ribosomes, as a rule, bind to the messenger RNA in the cap region and begin scanning, which is aimed at searching for start codons.
Introduction to Elongation
Translation in biology is a phased process, part of which we have already discussed in the paragraph on initiation. Now consider the elongation.
The growth process of the polypeptide type chain is carried out with the participation of two elongation factors, protein molecules. The first factor is the delivery of aminoacylated transport RNA to the ribosome A site. In eukaryotes, EF1a deals with this, and in prokaryotes, EF-Tu. The ribosome plays the role of a catalyst for peptide transfer from transport RNA to P and A sites, which are formed by peptide bonds by interaction with amino acid residues. This causes the growth of the peptide chain due to amino residues. Next, another protein enters the process, the role of which is to catalyze translocation. EF2 - eukaryotes, EF-G - prokaryotes. Translocation refers to the phenomenon of ribosome transfer along messenger RNA by 1 triplet. Upon completion of this pathway, the ribosome is again able to begin the elongation cycle.
The final stages of the synthesis
In biology, translation is not only the stages of initiation and elongation, but also termination. Which represents the final stage of protein synthesis. It proceeds on the ribosomal A site, and for this it is necessary to have one of the stop codons: UAA, UAG, UGA. In this case, the peptidyl transport RNA continues to be associated with the P site. At this point, the RF 1 and 2 proteins come into play, playing the role of catalysts for cleaving the polypeptide chain of nature from messenger RNA. There is also RF 3. It causes the dissociation of messenger RNA from ribosomes. Termination proceeds better with the uaa stop codon.
To summarize
Translation in biology (Cossack - sometimes you can find this name when searching, which is associated with numerous searches for people from the CIS countries) - is an extremely important process necessary for the synthesis of protein molecules. Without this process, it would be impossible to have life on planet Earth. Broadcast has a phased structure, uses a variety of proteins. Very different between pro and eukaryotes.