DNA Polymerase vs RNA Polymerase: Difference and Comparison

The polymerization process is essential for all organisms. It takes place in two different versions. One is DNA polymerase which is essential for the replication process in DNA.

And the other one is RNA polymerase, which is essential for transcription. Without these two, passing the gene from one generation to another will be difficult. 

Key Takeaways

1. DNA polymerase is an enzyme that helps in the replication and repair of DNA molecules, while RNA polymerase helps in the transcription of DNA into RNA molecules.
2. DNA polymerase requires a primer to initiate its activity, while RNA polymerase does not require a primer.
3. DNA polymerase can only add nucleotides in the 5′ to 3′ direction, while RNA polymerase can add nucleotides in both the 5′ to 3′ and 3′ to 5′ directions.

DNA Polymerase vs RNA Polymerase

DNA polymerase synthesizes new strands of DNA using complementary base pairing rules, proofreading, and error-correcting mechanisms. RNA polymerase is an enzyme that synthesizes RNA from DNA templates during transcription by adding nucleotides to the 3′ end of the growing RNA strand.

DNA polymerase is an enzyme that creates DNA polymerase by creating nucleotides. Nucleotides are the building blocks of DNA.

During DNA replication, these enzymes are essential, working in pairs to create two DNA strands. The strands are created from the original DNA molecule. The first three types of DNA polymerase are used in proofreading. 

RNA Polymerase is a group of enzymes that uses DNA or RNA as a synthesis template. To accomplish their task, they interact with many types of proteins.

RNAP 4 and 5 are found in plants. It has helicase activity, meaning no separate enzyme is needed for unwinding DNA. RNA polymerase has been found in many viruses as well. 

Comparison Table

Parameters of Comparison	DNA Polymerase	RNA Polymerase
Nucleotides	It uses DNA nucleotides for new strand synthesis.	It uses RNA nucleotides for new strand synthesis.
New strand	It will not be able to initiate a new strand.	It can initiate a new strand.
Use	It is used for DNA replication.	It is used for transcription.
Synthesization	It uses a double-stranded molecule.	It uses a single-stranded molecule.
Primer	It uses primer for the initiation of replication.	It does not use primer for the initiation of replication.

What is DNA Polymerase?

It is a group of enzymes that are used to catalyze the synthesis of DNA during replication. This process is very important for transferring genetic information from one generation to another.

They always work in pairs by replacing two strands of DNA in tandem. DNA polymerase has been divided into 5 types. DNA polymerase has two main functions.

It catalyzes the synthesis of DNA. It also helps in proofreading. It is an essential component used in PCR. The key role is that it is used for creating synthesized DNA strands.

But understanding the character of this enzyme and the development of advanced DNA polymerases are extremely critical. DNA polymerases are found in eukaryotic cells.

Without the help of DNA polymerase, the existing organisms cannot be able to replace and reproduce themselves.

This is because all organisms’ life depends on the information stored in DNA. Without DNA replication, information would not be able to pass on, and life will cease to exist.

The three main roles in DNA polymerase are polymerization, proofreading, and repair. The human genome encodes 14 DNA polymerases, which is a large number.

If DNA polymerase stops working, it will start to match with the wrong RNA polymerase, leading to many complications. 

What is RNA Polymerase?

It is a multi-unit enzyme. It uses transcription for synthesizing RNA molecules from a DNA template. This type of polymerase has been found in all types of species.

But the number and the composition of proteins in them will vary. For unwinding DNA, it binds into a gene region called a promoter. This will send the signal to DNA. This will help the enzyme to read the bases on any one of the DNA strands.

RNA Polymerase has been divided into 3 types. RNA polymerase comes from the nucleolus. It is a specialized nuclear structure where ribosomal RNA will be transcribed, assembled, and processed into ribosomes.

It acts as a catalyst for proofreading and transcription. In prokaryotic transcription, they will use the same RNA polymerase for transcribing all the genes. The polymerase is comprised of five sub-units called a holoenzyme.

The best part about RNA polymerase is it does not need a primer. It has no proofreading activity as it increases the mutation rate. The enzyme makes some mistakes. In the newly synthesized DNA, the mutations will remain the same.

Bacteria contain a single RNA polymerase type, whereas eukaryotic cells contain multiple RNA polymerase types. It belongs to the class of enzymes called nucleotidyltransferase. It produces chemical reactions while synthesizing RNA. 

Main Differences Between DNA Polymerase and RNA Polymerase

1. DNA polymerase has a very low error rate. On the other hand, RNA polymerase has a comparatively high error rate.
2. DNA polymerase is used for synthesizing the entire chromosome. On the other hand, RNA polymerase will stop the synthesis.
3. DNA polymerase cannot initiate a new strand. On the other hand, RNA polymerase is capable of initiating a new strand.
4. DNA polymerase uses a primer to begin the new process. On the other hand, RNA polymerase does not require a primer to begin the process.
5. DNA polymerase possesses exonuclease activity. On the other hand, RNA polymerase lacks exonuclease activity. 
6. DNA polymerase uses a double-stranded molecule for the replication process. On the other hand, RNA polymerase uses single-stranded molecules for the transcription process.

References

1. https://www.pnas.org/content/70/5/1326.short
2. https://www.sciencedirect.com/science/article/pii/0042682278902519