July 15, 2024
Medical Science

What is Ribonucleic acid (RNA)?


Last Update on September 15, 2022

| Overview |Types of RNA | Central Dogma | Structure of RNA | Functions of RNA | Diseases of RNA |

1. Overview:

All living cells contain ribonucleic acid (RNA). RNA is a nucleic acid with properties similar to DNA. However, RNA is often single-stranded, unlike DNA. Instead of the deoxyribose found in DNA, the backbone of an RNA molecule is consisting of alternating phosphate groups and sugar ribose.

Adenine, guanine, cytosine, and uracil are the nitrogenous bases found in Ribonucleic acid (RNA), which take the role of thymine in Ribonucleic acid (RNA).

Each sugar has one out of the four bases adenine (A), uracil (U), cytosine (C), or guanine (G) connected to it. Cells contain a variety of RNA types, including transfer RNA, messenger RNA, and ribosomal RNA (tRNA). However, specific RNAs control the appearance of genes. RNA acts as the genomic material for several viruses.

Ribonucleic acid (RNA) is the actual functional form of nucleic acids that the body actually uses to do the performance. The RNA is building cells or responding to immune challenges or even just carrying amino acids from one part of the cell to the other. RNA doesn’t always get the respect it merits.

Five carbons and one oxygen atoms make up the cyclical structure of the ribose sugar found in RNA. The second carbon group of the ribose sugar molecule has a chemically reactive hydroxyl (OH) group attached to it, which makes RNA susceptible to hydrolysis.

2. Types of Ribonucleic acid (RNA):

There are different types of RNA:

  • Transfer RNA
  • Messenger RNA
  • Ribosomal RNA (tRNA)

3. Central Dogma:

One of the three or four classes of essential “macromolecules” is thought to be essential for life; the nucleic acids are made up of Ribonucleic acid (RNA), short for ribonucleic acid, and DNA, short for deoxyribonucleic acid. The other two are lipids and proteins. Carbohydrates are also included in this category by several scientists. Large compounds known as macromolecules frequently have repeating subunits. Nucleotides are the building blocks for the development of RNA and DNA.

Together, the two nucleic acids form proteins. The creation of proteins utilizing the genetic material found in nucleic acids is considered by scientists to be “the central dogma” of molecular biology since it is so essential to life.

According to Oregon State University, the dogma—which defines the flow of genetic information in an organism—states that the information from DNA is “transcribed” as RNA, and the information from DNA is “translated” into protein.

4. Ribonucleic acid (RNA) structure:

RNA is normally a biopolymer with a single strand. The ribonucleotide chain is folded into complex structural forms with bulges and helices. As a result of intrachain base-pairing and the existence of self-complementary repeats in the RNA strand.

RNA structure

As a result of the ribose sugar and nitrogenous bases’ capacity to be transformed in a variety of ways by cellular enzymes that connect chemical groups (such as methyl groups) to the chain, the three-dimensional structure of RNA is essential to its stability and function. These changes make it possible for chemical interactions to develop between far-flung areas of the RNA strand, resulting in intricate twists in the RNA chain that further solidify the RNA structure.

Weakly stabilized and changing structural molecules are easily destroyed. As an illustration, alteration at position 58 of the tRNA chain in an initiator transfer RNA (tRNA) molecule that lacks a methyl group (tRNAiMet) causes the molecule to become unstable and hence nonfunctional; the nonfunctional chain is then eliminated by cellular tRNA quality control mechanisms.

Additionally, RNAs can join forces with ribonucleoproteins to create complexes (RNPs). It has been shown that the RNA part of at least one cellular RNP serves as a biological catalyst, a role formerly held only for proteins.

5. Functions of Ribonucleic acid (RNA):

Nearly every component of a cell comes into contact with RNA in some way. Ribonucleic acid (RNA) performs a wide range of tasks, including regulating gene activity during development, cellular differentiation, and changing environmental conditions. It also translates genetic information into molecular mechanisms and cell structures.

A particular polymer is a Ribonucleic acid (RNA). Similar to DNA, it uses complementary base pairing to connect to either DNA or RNA with high specificity. Amazingly, Ribonucleic acid (RNA) may catalyze chemical events, such as the combining of amino acids to form proteins. It can also bind specific proteins or tiny molecules.

All of the Ribonucleic acid (RNA) found in cells is a copy of a Genetic code found in the chromosome gene of the cell. Coding genes are generally referred to as genes that copy—or “transcribe”—the instructions for constructing distinct proteins. Therefore, “non-coding RNA” genes are those that create RNAs that are employed for other functions.

The information found in the cell’s DNA is translated into useful gene products like proteins by a number of important kinds of RNA molecules. Messenger RNAs (mRNAs) are amplified readouts of the nucleic acid sequences of individual protein-coding genes. They are copies of specific protein-coding genes.

Some RNAs can directly catalyze RNA modification processes due to their inherent enzymatic activity. Among these catalytic RNAs are several self-splicing RNA transcripts, ribozymes, and RNAse P, an RNA enzyme that practically all cells use to trim the ends of tRNA precursors.

The foundation for a large portion of cellular and organism structure, differentiation, and physiology is the regulation of the creation of proteins from coding genes. Numerous kinds of non-coding RNAs have a variety of roles in the regulation of gene activity at different levels, influencing the synthesis, stability, or translation of particular mRNA gene products.

The protection of the cell from viruses transposes, and other nucleic acid sequences that can threaten cellular homeostasis or genome stability is one of the main functions of certain groups of short non-coding RNAs. Some cells produce siRNAs that are complementary to the virus in response to viral infection.

6. RNA in diseases:

Ribonucleic acid (RNA) and human disease have been related in significant ways. For example, as was previously mentioned, some miRNAs have the ability to regulate cancer-related genes in ways that promote the formation of cancer.

Protein aggregation and neurodegeneration have historically been closely related. Certain types of aggregates or additions are detectable under a microscope in the majority of neurodegenerative disorders.

In addition, a number of neurological disorders, including Alzheimer’s disease, have been related to the deregulation of miRNA metabolism. The tRNAs can attach to specific proteins called caspases, which are involved in the apoptosis process, in the case of other RNA types (programmed cell death).

The ability of cells to resist programmed death signaling is a distinguishing feature of cancer, and tRNAs prevent apoptosis by attaching to caspase proteins. Cancer-related tRNA-derived fragments (tRFs), commonly known as non-coding RNAs, may also be involved.

New classes of tumor-specific RNA transcripts have been discovered as a result of the development of techniques like RNA sequencing, including MALAT1 (metastasis-associated lung adenocarcinoma transcript 1), whose elevated levels have been discovered in a variety of cancerous tissues and are linked to the spread and metastasis (spread) of tumor cells.

Repeat-containing RNAs have been shown to sequester RNA-binding proteins (RBPs), causing foci or aggregates to develop in brain tissues. These aggregates contribute to the emergence of neurological disorders such as myotonic dystrophy and amyotrophic lateral sclerosis (ALS).

Numerous human disorders have been linked to various RBPs’ loss of function, dysregulation, and mutation.

It is anticipated that more associations between RNA and illness will be found. Such discoveries are probably made possible by improved knowledge of RNA and its activities, ongoing advancements in sequencing technology, and attempts to identify RNA and RBPs as potential therapeutic targets.