what is RNA
RNA is the acronym for Ribonucleic Acid , an essential macromolecule for various biological functions.
As its name suggests, RNA is a nucleic acid (as well as DNA) and works in the regulation, coding and decoding of genes.
These acids, along with carbohydrates, lipids and proteins, make up the group of substances essential for all forms of life.
The main function of RNA is to produce proteins from the acquired DNA information .
For this reason, one of the great assumptions of molecular biology is that “ DNA makes RNA make proteins ”.
RNA is synthesized from DNA through the process of transcription.
This process begins with an enzyme called RNA polymerase , which promotes the opening of the DNA and ensures the pairing of the nucleotides that will be transcribed.
RNA is made up of a chain of smaller substances called nucleotides .
In RNA, nucleotides are made up of riboses, phosphates and nitrogenous bases which, in turn, are subdivided into:
- Purines: adenine (A) and guanine (G);
- Pyrimidines: cytosine (C) and uracil (U).
Differences between RNA and DNA
- The pentose (sugar) present in RNA is ribose, while in DNA it is deoxyribose.
- In RNA there is a nitrogenous base uracil, and in non-DNA there is thymine.
- The subtle difference in the pentose present in each acid gives DNA a higher level of stability, ideal for storing genetic information. On the other hand, the more unstable nature of RNA is sufficient for its short-term functions.
Types of RNA and their Functions
There are three types of RNA: Messenger (MRNA), Ribosomal (rRNA), and Carrier (tRNA).
Messenger RNA is the molecule responsible for carrying genetic information from DNA to the cytoplasm .
When a cell requires the production of a given protein, the DNA initiates the transcription process, through which the genetic code is copied, thus synthesizing a strand of Mrna.
This RNA functions as a mobile copy of the DNA that carries the message to the cytoplasm and informs the type of protein to be produced.
Ribosomal RNA is the substance that makes up about 60% of the rhizome , an organelle in which protein synthesis occurs.
Its function is to help in the translation of the information brought by the Messenger RNA.
Ribosomal RNA is synthesized in a dense region located in the nucleus of the cell, called the Nucleolus.
Carrier RNA (or transfer RNA) is the molecule responsible for carrying amino acids to the ribosome in order to aid in protein synthesis.
When the Messenger RNA informs the type of protein to be produced, the ribosomal RNA helps in the transfer of information to the carrier RNA .
Based on the codons (sequence of three nitrogenous bases), the genetic code is identified and the tRNA is responsible for transporting compatible amino acids for protein production.
In summary, the main characteristics of RNA are:
- Works on the regulation, coding and decoding of genes;
- Its main function is to produce proteins;
- They are formed by ribose, phosphates and nitrogenous bases;
- It is made up of a single chain (a ribbon);
- It can be classified as messenger RNA, ribosomal RNA, and carrier RNA.
- The Messenger is responsible for carrying the DNA information to the cytoplasm;
- Ribosomal RNA helps translate the information extracted from the DNA;
- Carrier RNA takes amino acids to the ribosome to aid in protein synthesis.
Differences between DNA and RNA