Describe the micrococcal nuclease assay. What are the 2 kinds of test we discussed and what does it show? Under which conditions would you see a single band? Ladder? Smear? The Micrococcal Nuclease Assay: Assessing DNA Fragmentation

The Micrococcal Nuclease Assay: Assessing DNA Fragmentation

The micrococcal nuclease (MNase) assay is a valuable tool used to assess DNA fragmentation. The assay is based on the ability of MNase to cleave double-stranded DNA into small fragments at random, thus providing a snapshot of the degree of DNA fragmentation. The assay consists of two types of tests performed in tandem: cleavage and electrophoresis. The cleavage step involves the use of MNase to break down DNA into smaller fragments, while the electrophoresis step separates the fragments of different sizes by running them through an agarose gel. In the presence of a single band, the MNase has cleaved the DNA into uniform-sized fragments. On the other hand, if the gel reveals a ladder-like pattern of bands, this indicates that the MNase has cleaved DNA into a variety of fragment sizes. Lastly, if the gel shows a smearing pattern, this suggests that the MNase has not cleaved the DNA at all (Schanbacher, 2017; Rios et al., 2020). Cont…