It requires an oligonucleotide primer and Mg or Mn. The avian enzyme possesses intrinsic ribonuclease H activity. Used for first strand synthesis of CDNA, primer extensions. Will not join single stranded nucelic acids. Nuclease - Cleaves duplex DNA and RNA with an exonuclease activity, from both ends and produces successively shorter strands.
Digestion gives mostly blunt-ends.
It will not degrade double stranded DNA with a 3'-overhang of at least four bases. The enzyme also has an endonuclease activity specific for apurinic sites, ribonuclease H activity, and a 3'phosphatase activity. Used for generating nested sets of deletlions with double stranded, linear DNA and for preparation of single-stranded DNA to serve as a template for dideoxy sequencing. Endonuclease IV - Multilple activities, all of which may be required for recombination or DNA repoar. Requires ATP for activity.