Question

Do eukaryotic cells have restriction endonucleases? Justify your answer.

Answer 1

No, eukaryotic cells do not have restriction endonucleases. These enzymes are found only in bacteria, where they serve as a defense mechanism against invading viruses by cutting foreign DNA at specific sites. In contrast, the DNA molecules of eukaryotes are heavily methylated, which protects them from such cleavage, and thus they do not produce restriction endonucleases.