Our genome takes the form of genes on the chromosomes that are found inside the cell nucleus. The genome is the same in all body cells and contains the blueprint for our whole body. Approximately 20,000 genes contain the blueprints for approximately 20,000 proteins. These proteins not only provide the body with structure and stability, but they also ensure that our body’s metabolism keeps running.
The genome therefore serves as a template for the production of proteins throughout the course of our lives and also ensures that our genetic blueprint is passed on to our children. Protein is also the most important substance in the body quantitatively, excluding water.
In terms of chemistry, chromosomes are composed of a long chain of a substance called deoxyribonucleic acid, which is abbreviated to DNA. This DNA chain is formed from the sugar ribose which is arranged like a string of pearls. Phosphorous serves as a link between the sugars. However, the genetic information is determined by four different molecules that contain nitrogen, known as ‘nitrogenous bases’ and one of these is bound to each ribose. The sequence of these different nitrogenous bases determines which protein this segment on the chromosome is forming the template for.
The chromosomes are packed in and protected in the nucleus of each body cell, however, the formation of proteins occurs outside the cell nucleus. The chromosomes are too large to penetrate through the tiny pores in the shell surrounding the nucleus to reach outside and there is no room in the cell nucleus itself for the proteins to form. This problem is solved when genetic information is transferred onto a short molecular chain which can leave the nucleus; this is the ribonucleic acid (RNA).
In terms of chemistry, RNA is closely related to DNA and it also consists of sugar-phosphate chains with nitrogen bonded bases. It has a few unique special features that are different from DNA, however, it also acts as a counterpart that complements the DNA precisely. RNA is therefore a short chain copy of a gene and is so small that the information required for the formation of protein can be transported to every location in the cell.
Proteins consist of chains of individual amino acids. 23 different amino acids provide the primary material for the formation of proteins and the exact sequence of these amino acids determines their function. The ribonucleic acid contains the blueprint for the sequence of these amino acids in the protein, i.e. the genetic information. It is particularly notable that nearly all living organisms use the same set form of translation in order to determine the sequence of amino acids in the protein from the sequence of bases in the ribonucleic acid.
This ‘translation’ is termed the ‘genetic code’ and is shown in the diagram. Described in simple terms, the translation functions in the following way: the ribonucleic acid which contains the blueprint for the protein is called messenger-RNA (m-RNA). Another special type of ribonucleic acid can transport amino acids and is called transfer-RNA (t-RNA). Precisely one of 23 possible amino acids are stuck to each transfer-RNA in each case and this arrangement is fixed, i.e. this transfer-RNA cannot transport other amino acids. Each type of transfer-RNA contains a segment with three bases which clearly shows which amino acids are bonded and are made available for protein synthesis. These specific three bases on the transfer RNA correspond with three bases on the messenger-RNA, i.e. on the RNA strand, which carries all the information required for a complete protein. The transfer-RNA bonds to the appropriate segment on the messenger-RNA. Neighbouring amino acids can then be attached to a chain and the sequence then matches the code on the messenger-RNA. The diagram shows the possible base sequences on the messenger-RNA with the associated amino acids. The diagram should be read from the inside to the outside. For example, if the bases uracil, guanine, guanine (U, G, G) are present in this sequence at one messenger-RNA location, a transfer-RNA will be bonded at this location that transports the amino acid tryptophan (trp). The genetic code determines the sequence of the amino acids in each protein. In addition, if there is an area on the messenger-RNA that contains the bases cytosine, uracil, uracil (C, U, U), a transfer-RNA is bonded with the amino acid leucine. The neighbouring amino acids tryptophan and leucine are then attached and become part of the chain that the protein will form.
Genetic matches in different living organisms are actually surprisingly high. Humans and apes have approximately 95% of their DNA in common. Humans and chickens share at least 60% of the same DNA. Even in yeast there are individual genes that have up to 50% of the same genetic code as the corresponding gene found in humans. New studies even show that even the short chain ribonucleic acids (micro-RNA) are identical or nearly identical in all mammals.
DNA is the data repository for all the information that a living organism needs; ribonucleic acid is the mode of transport for the precise pieces of information which a specific cell actually needs to form essential proteins. The formation of new proteins is required throughout the course of our lives because our body is constantly building up and breaking down. When these processes no longer function correctly, degeneration occurs and we begin to age.
Metabolic processes in body cells need to be activated when necessary or also inhibited. If all 20,000 genes which are present in the nucleus of every human cell were also used as a template for the formation of proteins, then metabolic processes in the cells would not function properly and we would not be able to live. The requirements needed to create this ordered metabolic system also vary in the different tissues. The cells require a specific protein for each specific task.
There are regulators in each cell which determine which gene is used for the production of protein. A multitude of regulators are known today, however, it has only been recently discovered that ribonucleic acids also undertake this task. Very short chains of no more than 20-25 sugars are particularly important in this case, which are known as micro-RNA. Micro-RNA has been studied intensively in recent years. It is now known that micro-RNA is necessary for both metabolism in the ‘day-to-day business’ of the cells in their role as regulators and that it is a key factor in determining which functions each cell and each tissue should undertake from the development of the first cells through to adulthood.
Prof. Dyckerhoff already isolated these ribonucleic acids 60 years ago. Current research shows that his production methods were also able to extract microRNA (Stommel et al. 2015). He made these natural RNA extracts into medications and laid the foundation for effective treatments. We will understand the underlying active mechanisms in even greater depth in the future.
Ribonucleic acids are currently being researched commercially on a large scale.
A major issue remains: can ribonucleic acids be used to channel other medications to the exact cells in which the medication is supposed to be effective? The goal is to use a particularly special characteristic of the ribonucleic acids that ensures that specific ribonucleic acids are only accepted by very specific cells. Enormous potential for the development of new medications is being seen.
A further development includes stable messenger-RNA molecules which are intended to serve as templates for missing proteins in the body. These sorts of proteins also include antibodies. The entire spectrum of illnesses that are influenced by the immune system could therefore benefit from these completely new types of treatment options.
Stommel G, Schühlein S, Schühlein KH, Rainsford KD (2015) Therapeutic Effects of Ribunucleinate (Ribonucleotides) in Immuno-Inflammatory and Arthritic Diseases in Progress in Drug Research, Vol. 70, K. D. Rainsford et al. (Eds): Novel Natural Products: Therapeutic Effects in Pain, Arthritis and Gastro-intestinal Diseases, pp 35-89; 978-3-0348-0926-9; (Medline:PMID: 26462364)