Question

DNA footprinting is based on the idea that certain DNA endonucleases degrade double‑stranded DNA to yield mononucleotides and dinucleotides, but these enzymes do not degrade those sequences to which other proteins are bound such as RNA polymerase. Why is this method done in the absence of ribonu­cleotide triphosphates?

Answer 1

Ans. - DNA footprinting is a technique where the double stranded DNA is cut by the enzymes endonucleases in between, so these form short nucleotides then, But these enzymes can only act if no other proteins are attached on DNA hence polymerase being present means the process of transcription is to occur.

so DNA footprinting is for identifying DNA-protein binding sites, RNA polymerase adds ribonucleotides for transcription which will affect its process of identification.

DNA footprinting is a method of investigating the sequence specificity of DNA-binding proteins in vitro.

This technique can be used to study protein-DNA interactions both outside and within cells. Basic RNA-binding peptides enhance ribozyme catalysis.

These enzymes mediate viral and cellular replication and antiviral defense in eukaryotes and prokaryotes, splicing, R-loop resolvation, DNA repair.

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