Polymerase stuttering is the process by which a polymerase

transcribe Transcription refers to the process of converting sounds (voice, music etc.) into letters or musical notes, or producing a copy of something in another medium, including: Genetics * Transcription (biology), the copying of DNA into RNA, the fir ...

s a nucleotide several times without progressing further on the

mRNA In molecular biology, messenger ribonucleic acid (mRNA) is a single-stranded molecule of RNA that corresponds to the genetic sequence of a gene, and is read by a ribosome in the process of synthesizing a protein. mRNA is created during the ...

chain. It is often used in addition of

poly A tail Polyadenylation is the addition of a poly(A) tail to an RNA transcript, typically a messenger RNA (mRNA). The poly(A) tail consists of multiple adenosine monophosphates; in other words, it is a stretch of RNA that has only adenine bases. In euka ...

s or capping mRNA chains by less complex

organism In biology, an organism () is any living system that functions as an individual entity. All organisms are composed of cells (cell theory). Organisms are classified by taxonomy into groups such as multicellular animals, plants, and ...

s such as viruses.

Process

A polymerase may undergo stuttering as a

probability Probability is the branch of mathematics concerning numerical descriptions of how likely an event is to occur, or how likely it is that a proposition is true. The probability of an event is a number between 0 and 1, where, roughly speakin ...

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 frameshifting, also known as translational frameshifting or translational recoding, is a biological phenomenon that occurs during translation that results in the production of multiple, unique proteins from a single mRNA. The process can ...

s on a slippery sequence of

nucleotide Nucleotides are organic molecules consisting of a nucleoside and a phosphate. They serve as monomeric units of the nucleic acid polymers – deoxyribonucleic acid (DNA) and ribonucleic acid (RNA), both of which are essential biomolecule ...

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

choke point In military strategy, a choke point (or chokepoint) is a geographical feature on land such as a valley, defile or bridge, or maritime passage through a critical waterway such as a strait, which an armed force is forced to pass through in order ...

s on both sides of the sequence.

Examples

A polymerase that exhibits this behavior is RNA-dependent RNA polymerase, present in many RNA viruses. Reverse transcriptase has also been observed to undergo this polymerase stuttering.

Literature

{{reflist Genetics