Ribothymidine is a nucleoside that is a building block of tRNA and rRNA. As such, it plays an important role in numerous metabolic processes.
What is ribothymidine?
Ribothymidine is also known as 5-methyluridine. It is a nucleoside. Nucleosides are single molecules of tRNA and rRNA that occur within cells. The tRNA or transfer DNA is like a tool that is used in the translation of DNA into amino acid chains. Each ribothymidine molecule is composed of two building blocks: a sugar molecule and a nucleic base. The sugar molecule is β-D-ribofuranose, which, among other things, consists of five carbon atoms. For this reason, biology also calls β-D-ribofuranose a pentose, after the Greek word for “five.” The basic structure of the molecule is a closed ring that is also pentagonal. The second building block of ribothymidine is thymine. Thymine is a nucleic base and is also an important component of human DNA, which stores genetic information. Together with adenine, thymine forms a base pair. The N1 atom of thymine bonds with the C1 atom of β-D-ribofuranose. The molecular formula for ribothymidine is C10H14N2O6.
Function, action, and roles
Ribothymidine and three other types of nucleosides make up tRNA and rRNA. The tRNA is the transfer ribonucleic acid. It helps in translation, the biological translation of DNA into protein chains. Translation relies on a copy of the genes. This copy is the messenger RNA or mRNA. Like deoxyribonucleic acid (DNA), it is a form of biological data storage. The mRNA originates inside the cell nucleus. It is an exact copy of DNA, which itself never leaves the cell nucleus. Specialized enzymes are responsible for copying; instead of the sugar deoxyribose, they use the sugar ribose for the mRNA. The finished mRNA migrates out of the cell nucleus and thus transmits the genetic information to the rest of the human cell. A so-called ribosome translates the information from the mRNA into a strand of proteins. The protein chain is composed of different amino acids. In total, there are twenty different amino acids that make up all the more complex protein molecules. A so-called triplet, i.e. three base pairs of DNA or RNA, codes for a specific amino acid in a distinctive way. In order for the ribosome to perform its task, it needs tRNA, which is a short chain of RNA. The tRNA transports amino acids. To do this, the tRNA binds an amino acid to its one end and docks with the other end to the matching triplet. The tRNA now connects mRNA and amino acid like a pin. The ribosome moves the loaded tRNA into position, one at a time. The amino acids join together by biochemical processes. The ribosome slides one triplet further and the tRNA detaches from the amino acid on one side and the mRNA on the other. The empty tRNA can now reattach to a new amino acid molecule and return the new building block to translation.
Formation, occurrence, properties, and optimal levels
Ribothymidine normally exists in the solid state. The human body can synthesize ribothymidine by combining a sugar molecule (ribose) with a nucleic base. While DNA is composed of the four bases adenine, guanine, cytosine and thymine, in RNA, uracyl replaces thymine as the fourth base. Uracyl is very similar to thymine. In their molecular structure, the two differ only in a single group (H3C). Both belong to the pyrimidine bases, the basic structure of which is a pyrimidine ring. This is a closed, ring-like structure with six corners and two nitrogen atoms. Although biology is familiar with ribothymidine and other nucleosides primarily in their capacity as RNA components, it also plays a role in other biological processes, as it also appears as a building block in macromolecules.
Diseases and disorders
Diseases that can occur in connection with ribothymidine include genetic defects. Radiation, chemical substances, and UV light can increase the likelihood of mutations. A mutation is an error in genetic information in which the DNA strand suffers damage.Such damage happens in the human body all the time, and usually certain enzymes detect and repair such irregularities. Occasionally, however, they overlook defects or are unable to repair them correctly or only incompletely. If the cell’s self-destruct mechanism also fails, it replicates and thereby also spreads the faulty genetic information. Such failures include, for example, the confusion or substitution of nucleic bases. As a result, the genes encode the wrong information, possibly disrupting central metabolic processes. Depending on the location of the DNA or RNA at which such an error occurs, the effects can vary greatly. Even tRNA, in which ribothymidine occurs as one of four nucleosides, can be subject to errors. For example, if ribothymidine is synthesized incorrectly, translation could be affected. Translation is the process that translates genetic information into proteins. In particular, errors in the ends of the tRNA fragment could result in the inability of the tRNA to bind correctly to the mRNA or amino acid that it is supposed to transport.
