The main difference between DNase and RNase is that DNase catalyses the breakdown of DNA molecules into smaller components, whereas RNase catalyses the breakdown of RNA molecules into smaller components.
DNA and RNA are the genetic material present in living organisms. The DNA and RNA molecules are made by joining nucleotides in a chain-like series. These nucleotides join phosphodiester bonds. The enzymes DNase and RNase can help to break down these long chains of DNA and RNA molecules into smaller compounds.
Key Areas Covered
1. What is DNase
– Definition, Types, Function, Features
2. What is RNase
– Definition, Function, Features
3. Difference Between DNase and RNase
– Comparison of Key Differences
Key Terms
DNA, DNase, DNase I, DNase II, RNA, RNase, Exoribonucleases, Endoribonucleases
What is DNase
DNase is an enzyme that catalyses the hydrolytic cleavage of phosphodiester linkages between nucleotides in the DNA backbone. DNases are often called deoxyribonucleases. They are a group of glycoprotein endonucleases. Moreover, the main function of DNases is to degrade the DNA molecule.
Types of DNases
There are two types of DNases known as DNase I and DNase II. This is due to the encoding of the DNase gene by two different DNase genes that are different in length and number of exons. DNase 1 is an endonuclease encoded by the gene DNASE1 secreted by the pancreas. This DNase1 digests extracellular nucleoproteins, which results in reduced autoimmune reactions and DNA fragmentation during DNA apoptosis. DNase II is also known as acid DNase. People also call it nicking DNase because it can cleave both strands of the DNA. There are two types of DNase II; alpha and beta DNase. This DNase II is present in human cells and in minute quantities in saliva, blood, and testicular liquid.
Based on the type of DNase that acts on the DNA, they either produce 3′ hydroxyl and 5′ phosphate ends or vice versa. It could be with either a sticky or blunt end after the cleavage process. DNA also could be classified into two groups depending on the presence of DNA in a particular location. They are extracellular DNase and intracellular DNase. The extracellular DNase is outside the living organisms and is present in a variety of environments like oceans, soil, and freshwater. Intracellular DNase, on the other hand, is the enzyme found within organisms.
There are different methods DNases use to cleave DNA. Some DNases cleave at the end, whereas some cleave anywhere in the DNA strand. Some cut at specific sequences, while some cut at any sequence. Moreover, some DNases cleave single-stranded DNA, whereas some cleave double-stranded DNA.
In laboratories, these DNases are used to perform many functions like labelling antibodies, plasmid preparation and purification, RNase-free footprinting, preparation of DNA-free RNA, as well as the removal of template DNA after in-vitro transcription.
What is RNase
RNase is a hydrolytic enzyme that catalyses both the in vivo and in vitro degradation of ribonucleic acid molecules (RNA) into smaller components. It cleaves the phosphorous oxygen bond between nucleotides, operating at a level of transcription and translation. These RNase can be categorised into two types; exoribonucleases and endoribonucleases. An exoribonuclease is an exonuclease ribonuclease that degrades RNA by removing terminal nucleotides from either the 5′ ends or the 3′ ends of the RNA molecule. These RNase have six types of nucleases, including RNase D, RNase R, and RNase T. Meanwhile, endoribonucleases (endonuclease ribonuclease) break down RNA molecules internally. They break single-stranded or double-stranded RNA. Additionally, there are several forms of endoribonuclease that differ according to their structure. Some of them may consist of a single protein or many proteins together with RNA.
These RNase types have several different functions. For example, RNase T is the contributor to the 3′-5′ maturation of many stable RNAs, while RNase R degrades secondary structures of RNA without any help from accessory factors, and RNase III takes part in the regulation of transcription and mRNA lifetime.
Difference Between DNase and RNase
Definition
DNase is an enzyme that catalyses the hydrolytic cleavage of phosphodiester linkages between nucleotides in the DNA backbone, while RNase is a hydrolytic enzyme that catalyses both the in vivo and in vitro degradation of ribonucleic acid molecules (RNA) into smaller components.
Function
DNase catalyses the breakdown of DNA molecules into smaller components, whereas RNase catalyses the breakdown of RNA molecules into smaller components.
Types
DNases have two types of enzymes; DNase I and DNase II, while RNases have two main types of enzymes; endoribonuclease and exoribonuclease.
Substrate Specificity
DNases are specific to DNA, whereas RNases are specific to RNAs.
Optimal pH
Most DNases function in slightly alkaline environments (pH 7.5-8.5), whereas RNases function in slightly acidic environments (pH 5-6).
Structure
DNases are larger and have more complex structures, whereas RNases have smaller and comparatively simpler structures than DNases.
Conclusion
DNA and RNA are two genetic materials found in living organisms. These large chains of molecules can be cleaved using enzymes like DNase and RNase. The main difference between DNase and RNase is that DNase catalyses the breakdown of DNA molecules into smaller components, whereas RNase catalyses the breakdown of RNA molecules into smaller components.
Reference:
1. “Structure of acid deoxyribonuclease.” National Library of Medicine.
2. “Biological Activities of Secretory RNases: Focus on Their Oligomerization to Design Antitumor Drugs.” Frontiers of Immunology.
Image Courtesy:
1. “DNase II” By Oliviasw – Own work (CC BY-SA 4.0) via Commons Wikimedia
2. “RNase A” – Vossman assumed – No machine-readable source provided. Own work assumed (based on copyright claims). (CC BY-SA 2.5) via Commons Wikimedia
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