Polymerase stuttering is the process by which a polymerase

Polymerase

A polymerase is an enzyme whose central function is associated with polymers of nucleic acids such as RNA and DNA.The primary function of a polymerase is the polymerization of new DNA or RNA against an existing DNA or RNA template in the processes of replication and transcription...

 transcribe

Transcription (genetics)

Transcription is the process of creating a complementary RNA copy of a sequence of DNA. Both RNA and DNA are nucleic acids, which use base pairs of nucleotides as a complementary language that can be converted back and forth from DNA to RNA by the action of the correct enzymes...

s a nucleotide several times without progressing further on the mRNA chain. It is often used in addition of poly A tails or capping

5' cap

The 5' cap is a specially altered nucleotide on the 5' end of precursor messenger RNA and some other primary RNA transcripts as found in eukaryotes. The process of 5' capping is vital to creating mature messenger RNA, which is then able to undergo translation...

 mRNA chains by less complex organism

Organism

In biology, an organism is any contiguous living system . In at least some form, all organisms are capable of response to stimuli, reproduction, growth and development, and maintenance of homoeostasis as a stable whole.An organism may either be unicellular or, as in the case of humans, comprise...

s such as viruses.

Process

A polymerase

Polymerase

A polymerase is an enzyme whose central function is associated with polymers of nucleic acids such as RNA and DNA.The primary function of a polymerase is the polymerization of new DNA or RNA against an existing DNA or RNA template in the processes of replication and transcription...

 may undergo stuttering as a probability

Probability

Probability is ordinarily used to describe an attitude of mind towards some proposition of whose truth we arenot certain. The proposition of interest is usually of the form "Will a specific event occur?" The attitude of mind is of the form "How certain are we that the event will occur?" The...

 controlled event, hence it is not explicitly controlled by any mechanisms in the translation process. Generally, it is a result of many short repeated frameshift

Ribosomal frameshift

A ribosomal frameshift allows alternative translation of a mRNA sequence by changing the open reading frame. It is commonly found in viruses including barley yellow dwarf virus, potato leafroll virus and simian retrovirus-1. Ribosomal frameshifting is promoted by a pseudoknot structure and slippery...

s on a slippery sequence of nucleotide

Nucleotide

Nucleotides are molecules that, when joined together, make up the structural units of RNA and DNA. In addition, nucleotides participate in cellular signaling , and are incorporated into important cofactors of enzymatic reactions...

s on the mRNA strand. However, the frameshift is restricted to one (in some cases two) nucleotides with a pseudoknot

Pseudoknot

A pseudoknot is a nucleic acid secondary structure containing at least two stem-loop structures in which half of one stem is intercalated between the two halves of another stem. The pseudoknot was first recognized in the turnip yellow mosaic virus in 1982...

 or choke point

Choke point

In military strategy, a choke point is a geographical feature on land such as a valley, defile or a bridge, or at sea such as a strait which an armed force is forced to pass, sometimes on a substantially narrower front, and therefore greatly decreasing its combat power, in order to reach its...

s on both sides of the sequence.

Examples

A polymerase that exhibits this behavior is RNA-dependent RNA polymerase

RNA-dependent RNA polymerase

RNA-dependent RNA polymerase , , or RNA replicase, is an enzyme that catalyzes the replication of RNA from an RNA template...

, present in many RNA viruses. Reverse transcriptase

Reverse transcriptase

In the fields of molecular biology and biochemistry, a reverse transcriptase, also known as RNA-dependent DNA polymerase, is a DNA polymerase enzyme that transcribes single-stranded RNA into single-stranded DNA. It also helps in the formation of a double helix DNA once the RNA has been reverse...

has also been observed to undergo this polymerase stuttering.