DNase

Definition

An enzyme (deoxyribonuclease) that catalyzes the hydrolytic cleavage of phosphodiester bonds in DNA, degrading it into smaller oligonucleotide fragments. DNases are classified by cleavage pattern (endonucleases vs. exonucleases), cofactor requirements, and sequence specificity. In arthropod biology, DNase I is routinely used to eliminate contaminating DNA during RNA extraction from insect or arachnid tissues, and research into extracellular DNA degradation informs studies of invertebrate immune mechanisms analogous to neutrophil extracellular traps.

Etymology

Abbreviation of deoxyribonuclease, from deoxyribonucleic acid (DNA) + -ase (enzyme suffix)

Example

When preparing transcriptomes from spider silk glands, researchers treat lysates with DNase to remove genomic DNA contamination before RNA sequencing.

Synonyms

• deoxyribonuclease

Related Terms

• RNase
• endonuclease
• exonuclease
• extracellular DNA
• apoptosis
• nucleic acid extraction
• NETosis

Usage Notes

DNase I (non-specific, requires divalent cations) is the most common laboratory form; distinguish from sequence-specific DNases used in molecular cloning. In field and lab settings, DNase treatment is essential when DNA contamination would confound RNA-based analyses (qPCR, RNA-seq) or when purifying proteins from prokaryotic expression systems. Not to be confused with Dnase (lowercase) gene nomenclature in some databases.