T4 DNA Polymerase catalyzes the 5'-->3' synthesis of DNA from a primed single-stranded DNA template. Although possessing a potent 3'-->5' proofreading exonuclease, T4 DNA Polymerase contains no 5'-->3' exonuclease activity. T4 DNA Polymerase can be used to fill 5' protruding ends with labeled or unlabeled dNTPs or for the generation of blunt ends from DNA molecules with 3' overhangs.
