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Messenger ribonucleic acid (mRNA) is a molecule of ribonucleic acid (RNA) that encodes the correct sequence of amino acids in a protein. It is a copy of a DNA sequence, which is located in the genetic material in the nucleus of a cell. After messenger RNA is created, it is transported to a protein construction site in the body of the cell, called a ribosome. The ribosome reads the messenger RNA and translates it into a protein.
All life forms contain three large macromolecules, one of which is messenger RNA. It essentially is a long chain of subcomponents called nucleotides. The specific sequence of nucleotides encodes information that messenger RNA carries from one place to another.
The master blueprint for an organism is contained in its DNA. DNA is the long-term storage for all of the various sequences of amino acids that are needed to construct an organism. These information sequences are popularly called genes.
Ribosomes have the ability to construct proteins but not the information necessary to construct a specific protein. In this way, they are a like a computer without a program. When a protein is needed, a section of DNA must be copied and delivered to the ribosome. The messenger RNA is this copy, and it acts like the software needed to create a protein. Inside the ribosome is a soup of amino acid components that will be connected together to make a specific protein.
Human messenger RNA lasts from one minute to several days. It is created during a process called transcription and lasts until the protein is constructed. After that, it breaks up in a process called degradation. Between transcription and degradation, a number of other processes might take place.
An active RNA begins with a cap, which is bound to the beginning of the mRNA at the time transcription begins. Sometimes the DNA that was copied has sections that do not contain any useful information. Before the mRNA is used, these sequences are removed in a process called splicing.
In some cases, a messenger RNA is "edited" by inserting a marker that terminates construction before the end of the sequence is reached. Editing creates a shortened version of the protein. At the end of its life, the cap is removed from the mRNA, after which the cell no longer uses it.
Copying genetic information requires several other types of RNA. The first is ribosomal RNA, which decodes the messenger RNA into individual amino acids. This happens at the synthesis site in the ribosome. The second type is transfer RNA, which stitches together the needed amino acids in the sequence dictated by the mRNA.
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