Transcriptomics: Open Access
Open Access

Synthesis, Processing and Functions of mRNA

Patrick John^{* *}Correspondence: Patrick John, Department of Biotechnology, Aichi Cancer Center, Aichi, Japan, Email:

Author info »

Description

A messenger ribonucleic acid (mRNA) molecule is a singlestranded RNA molecule that corresponds to a gene's genetic sequence and is read by a ribosome during the protein polymerization reaction. mRNA is produced during the transcription process, when an enzyme called RNA polymerase turns the gene into main transcript mRNA (also known as premRNA). Introns, or sections of the pre-mRNA that will not code for the final amino acid sequence, are generally still present. These are eliminated during the RNA splicing process, leaving only exons, or protein-coding regions. The mature mRNA is made up of this exon sequence. The ribosome reads mature mRNA, and the ribosome builds the protein using amino acids carried by transfer RNA (tRNA) by a process called Translation. All of these processes are part of molecular biology's fundamental dogma, which outlines how genetic information moves through a biological system.

Transcription

It is the process of duplicating RNA from DNA. RNA polymerase makes a copy of a gene from DNA to mRNA as needed during transcription. In eukaryotes and prokaryotes, this process differs slightly. One major difference is that during transcription, prokaryotic RNA polymerase binds with DNAprocessing enzymes, allowing processing to continue while transcription is taking place. As a result, the new mRNA strand becomes double stranded, creating a complementary strand known as the tRNA strand, which cannot create structures from base-pairing when coupled. Furthermore, the complementary strand of tRNA serves as the template for mRNA, and it is identical in sequence to the anticodon sequence that the DNA binds to precursor mRNA, or pre-mRNA, is a short-lived, unfinished or partially processed product.

Eukaryotic pre-mRNA processing

Eukaryotes, bacteria, and archaea all have different ways of processing mRNA. Except in exceptional situations, noneukaryotic mRNA is mature upon transcription and does not need to be processed. However, before being transported to the cytoplasm and translated by the ribosome, eukaryotic pre-mRNA must go through multiple processing steps.

• Splicing

• 5’ cap addition

• Editing

• Polyadenylation

Transport

The transport of mRNA is another distinction between eukaryotes and prokaryotes. Because eukaryotic transcription and translation are segregated, eukaryotic mRNAs must be exported from the nucleus to the cytoplasm, a process that can be influenced by a variety of signalling pathways. Mature mRNAs are identified by their processed modifications and subsequently exported through the nuclear pore by binding to the cap-binding proteins CBP20 and CBP80, as well as the transcription/export complex (TREX). In eukaryotes, many mRNA export mechanisms have been discovered.

In spatially complex cells, some mRNA is transported to specific intracellular targets. In mature neurons, certain mRNAs are transported from somatic cells to dendrites. One site of mRNA translation is on polysomes that are selectively localized under synapses. Arc / Arg3.1 mRNA is induced by synaptic activity and selectively localizes nearby active synapses based on signals generated by NMDA receptors. Other mRNAs also move within the dendrites in response to the following external stimuli: B. β- actin mRNA. When exported from the nucleus, actin mRNA binds to the ZBP1 and 40S subunits. Complexes are bound by motor proteins and transported along the cytoskeleton to the target site (neurite process). Finally, ZBP1 is phosphorylated by Src to initiate translation. In developing neurons, mRNA is also transported to growing axons, especially growth cones. Many mRNAs are labeled with so-called "zip codes" that are targeted for transport to specific locations.

Applications

A nucleoside-modified messenger RNA sequence can lead a cell to produce a protein, which could be used to treat a disease or serve as a vaccination; more indirectly, the protein could cause an endogenous stem cell to develop in a desired manner. The most difficult aspect of RNA therapy is getting the RNA to the right cells.

The fact that naked RNA sequences decay spontaneously after preparation, they may stimulate the body's immune system to attack them as an invader, and they are impermeable to the cell membrane are all challenges.