What is Reverse Transcriptase? What enzymes are needed for reverse transcription

Reverse transcription: also known as reverse transcription, the process of synthesizing DNA using RNA as a template, is a replicating form of RNA virus, catalyzed by reverse transcriptase. In the process, the mature mRNA with intron removal by shearing is used as a template to synthesize RNA DNA hybrid double strands, then the RNA strands are hydrolyzed, and then the remaining DNA single strands are used as a template to synthesize DNA double strands.

Reverse transcriptase

Also known as RNA-directed DNA polymerase. It is an enzyme that uses RNA as a template to synthesize DNA. This enzyme was discovered in 1970 by the American scientists Temin (and Baltimore) in animal carcinogenic RNA viruses, for which they were awarded the 1975 Nobel Prize in Physiology or Medicine.

When an RNA oncogenic virus, such as Rous sar-coma virus in birds, enters the host cell, its reverse transcriptase first catalyzes the synthesis of a single strand of DNA complementary to the viral RNA, and then replicates the double-helix DNA, which is integrated into the host's chromosomal DNA by the action of another viral enzyme. Some of it serves as the genetic material of the virus, and the other part is translated into virus-specific proteins as mRNA. Finally, RNA and proteins are assembled into new virions. Under certain conditions, integrated DNA can also enable cells to transform into cancer cells.

Using DNA as a template, under the catalysis of RNA polymerase, the formation of RNA is called transcription, and reverse transcription, as the name suggests, is to use RNA as a template to form the corresponding DNA under the action of reverse transcriptase.

Also known as: rna

Directed. dna

Polymerase, is based on.

RNA is an enzyme that synthesizes DNA from a template. Viruses that contain reverse transcriptase are called retroviruses, and reverse transcriptase-catalyzed reactions are called reverse transcriptions.

In this process, the direction of the flow of genetic information is from. RNA to.

DNA, which is the opposite of the transcription process, is called reverse transcription.

The process of synthesizing DNA using RNA as a template, which usually occurs when an RNA virus infects a host cell, and the synthesized DNA is integrated into the DNA of the host cell.

<> process of reverse transcription requires reverse transcriptase to be catalyzed. This reverse transcriptase, also known as RNA-dependent DNA polymerase (RDDP), catalyzes the synthesis of DNA strands using RNA as a template. The synthetic DNA strand is called ComplementaryDNA (cDNA) with RNA.

Reverse branching is present in some RNA viruses and may be involved in the malignant transformation of the virus.

The human immunodeficiency virus (HIV) is also an RNA virus that contains reverse transcriptase. Reverse transcriptase is also found in normal cells and embryonic cells of mice and humans, and it is speculated that it may be related to cell differentiation and embryonic development.

The role of reverse transcriptase is to use dNTP as the substrate, RNA as the template, and tRNA (mainly tryptophanic pure gallic acid tRNA) as the primer, in tRNA3'- On the end, press 5'→3'direction, synthesizing a single strand of cDNA that is complementary to the RNA template, which forms an RNA-cDNA hybrid. Subsequently, under the action of reverse transcriptase, the RNA strand is hydrolyzed, and the second DNA strand is synthesized using cDNA as a template. At this point, the RNA synthesis process guided by RNA is completed.

The three roles of reverse transcriptase:

Anti-excitation 1, RNA as template-guided DNA polygenase activity;

2. DNA as template-guided DNA polymerase activity;

3. RNaseh activity.

RNA-directed DNA polymerase activity; Using RNA as a template, catalyze the process of polymerization of DNTP into DNA. This enzyme requires RNA as primers, mostly tryptophan tRNA, so it has no correction function, so the error rate of DNA catalyzed by reverse transcriptase is relatively high.

rnaseh activity; The hybrid molecule formed by the synthesis of cDNA catalyzed by reverse transcriptase with template RNA will hydrolyze the RNA molecule from the 5th end of the RNA by RNAseh.

DNA-directed DNA polymerase activity; Using the first single strand of DNA synthesized by reverse transcription as a template, Li Lushen used DNTP as a substrate to synthesize the second DNA molecule.

Reverse transcriptase and reverse transcriptase are the same concept, but the translation is not the same.

Reverse transcripatase: (reverse transcripatase) is an enzyme that uses RNA as a template to guide the synthesis of complementary DNA (cDNA) by deoxynucleotides triphosphate. The reverse transcriptase of mammalian C virus and the reverse transcriptase of murine B virus are both polypeptide chains.

The reverse transcriptase of avian RNA viruses consists of two upper subunits. Reverse transcriptases with different structures have also been isolated in eukaryotes.

All of the inverted macroguessases have a variety of enzymatic activities, mainly including the following activities:

DNA polymerase activity; Using RNA as a template, catalyze the process of polymerization of DNTP into DNA. This enzyme requires RNA as primer, mostly tryptophan tRNA, to synthesize DNA in the 5-3 direction at the tRNA 3-end of primers. Reverse transcriptase does not have 3 5 exonuclease activity, so there is no correction function, so the error rate of DNA catalyzed by reverse transcriptase is relatively high.

rnaseh activity; The hybrid molecule formed by the synthesis of cDNA catalyzed by reverse transcriptase with template RNA will hydrolyze the RNA molecule from the 5th end of the RNA by RNAseh.

DNA-directed DNA polymerase activity; The first DNA single strand synthesized by reverse transcription was used as a template, and the second DNA molecule was synthesized with DNTP as the substrate.