Transcription vs. Reverse Transcription

Main Difference

The main difference between transcription and reverse transcription is that transcription is the converting of the DNA genome into RNA molecules, whereas transcription is the changing of the RNA genome into DNA molecules.

Difference Between Transcription and Reverse Transcription

Comparison Chart

Transcription vs. Reverse Transcription

Transcription is the method of replicating the genetic information from the DNA genome into RNA complementary strand; on the other hand, reverse transcription is the method in which RNA template is replicated into cDNA molecule in retroviruses. Transcription process occurs in both prokaryotes like bacteria, etc. and in all eukaryotes; on the contrary, reverse transcription occurs only in retroviruses when they enter the host body. Transcription is considered as the converting of DNA genome into RNA molecule; on the flip side; reverse transcription is generally considered as the converting of the RNA genome into the DNA molecule.

Transcription happens in the nucleus of eukaryotes and cytoplasm of prokaryotes; on the other hand, reverse transcription happens in the cytoplasm of the host when retrovirus enters into the host body. In transcription, RNA polymerase enzyme is involved in the transcription of the DNA genome into RNA molecule; on the other hand, in reverse transcription, reverse transcriptase enzyme is involved. RNA polymerase does not use any primer during the process of transcription; on the contrary, reverse transcriptase involves Lysyl tRNA, which acts as the primer of reverse transcriptase in the reverse transcription process.

The transcription is lined by 3’ UTR, 5’ UTR, and a poly-A tail; on the flip side, the reverse transcription is linked through long terminal repeats (LTRs). Transcription consists of wide importance in the body of prokaryotes and eukaryotes because it carries out the process of protein synthesis; on the other hand, the importance of reverse transcriptase is vital in retrovirus because of the products of reverse transcriptase are integrated into the host genome. The template used in transcription is DNA; on the other hand, the template used in reverse transcription is RNA.

In transcription, its end product is mRNA; on the contrary, in reverse transcription, the end product is complementary DNA. The function which transcription performs is to manufacture mRNA to be translated into proteins; on the other hand, the functions performed by reverse transcriptase is to manufacture the complementary DNA, and this process is mainly used in vivo to recognize the encoding sequences of DNA and then arrange them into collections of cDNA.

What is Transcription?

Transcription includes the synthesis of a duplicate of genetic information which is stored in DNA genomes into a corresponding strand of RNA. The enzyme which is involved in the transcription process is RNA polymerase. The transcription process is present parallel and complementary to the template of the strand. mRNA is formed as the main type of RNA.

The dictation of genes that are coded for protein synthesis usually results in the formation of mRNAs. The formed mRNA is translated throughout protein production to form an amino acid arrangement of a functional protein. Additionally, tRNA and rRNA have also translated that assist in the formation of proteins.

Transcription Mechanism

• Initiation: The process is started by the binding of RNA polymerase into the developer of the gene with the assist of related proteins known as transcription factors. Activators and repressors are used in the initiation of the transcription process.
• Promotor Escape: After the production of the transcription initiation compound, some nucleotides are added to the novel strand, and RNA polymerase discharges from the promoter.
• Elongation: After the discharge of the promoter, the transcription elongation is immediately produced.
• Termination: At the transcription finish site for the finishing of the process, the primary transcript is cut off from the template.

What is Reverse Transcription?

Reverse transcription is the process in which the RNA genome is copied into a cDNA molecule in retroviruses. This process is also known as the reverse of transcription. The reverse transcription starts with entering of specific particles into the host.

The process of reverse transcription happens in the cytoplasm of the host of retroviruses. The cDNA which is formed is combined into the genome of the host for continuing the replication protein synthesis process. The reverse transcriptase enzyme is involved in the process of reverse transcription.

Mechanism of Reverse Transcription

• The primer of the reverse transcription Lysyl combined with the primer binding site (PBS) of the RNA genome.
• Reverse transcriptase forms the non-coding (U5) and R areas of the viral RNA by added nucleotides to the 3’end of the primer.
• The primer ‘jumps’ towards the 3’ end of the RNA genome, crossing the recently composed DNA with the R area of the 3’end of the genome.
• The reverse transcriptase enzyme then forms the cDNA by adding nucleotides.
• The degradation of tRNA occurs.
• The formation of both strands is finished by the DNAP role of reverse transcriptase.

Conclusion

The above discussion concludes that the transcription is the method of encoding the DNA genome into RNA molecule which is used in protein synthesis. Reverse transcription is the process of encoding the RNA genome into the DNA molecule when a retrovirus enters into the host cell. Transcription happens in prokaryotes and eukaryotes, while reverse transcription occurs only in retroviruses.