Cleavage of a radioactively labeled single- and double-stranded DNA by tear lipocalin and EndoA

Copyright information:Taken from "Tear lipocalin is the major endonuclease in tears"Molecular Vision 2008;14():180-188.Published online 29 Jan 2008PMCID:PMC2254967. : A 32-mer oligonucleotide was digested by TL (lanes 1–3), the minor tear endonuclease (lanes 5–7), or DNase I (lanes 6–9) at 5, 10, and 20 min, respectively. The lane designated M shows oligonucleotide sizing markers. The size of the single strand digestion products differ for the three enzymes. : A 211 bp PCR product was digested by TL (lanes 1, 2, 3), DNase I (lanes 1’, 2’, 3’), or the minor endonuclease (lanes 1”, 2”, 3”) in 10, 20, and 30 min, respectively. The lane headings, A, T, G, and C, identify the respective base-specific sequencing reactions. Sequencing was performed using the dideoxy method with T7 DNA-polymerase. The corresponding sequence of the dsDNA is shown (left). The varying intensity of the bands at the sequences shown reflect different rates of cleavage related to relative sequence preferences for each of the three enzymes.