title: Characterization of single-stranded regions in DNA from injured tissue.
abstract: The objective of this study was to characterize the previously demonstrated decrease in the molecular weight of DNA from kidneys submitted to storage injury. DNA from kidneys stored at either 0 degrees C for 24-96 hr or 37 degrees C for 1-3 hr underwent limited hydrolysis when incubated with S1 nuclease, an enzyme which specifically degrades single-stranded DNA. For warm-storage injury (37 degrees C), the susceptibility of the DNA toward S1 nuclease hydrolysis increased progressively with storage time. In the case of cold-storage injury (0 degrees C), a maximum degree of single strandedness was observed in the DNA representing 60 hr of storage. DNA from kidneys stored for 72 hr or longer was a poor substrate for S1 nuclease. Additionally, the nucleotide composition of the single-stranded regions was analyzed by high-performance liquid chromatography (HPLC). The results showed that single-stranded regions initially rich in dA and dT are formed during warm-storage injury. No such favoritism for a particular base was observed in single-stranded regions produced during cold-storage injury. The data suggest that both warm- and cold-storage injury promote DNA degradation. The storage temperature apparently dictates the mechanism(s) by which the degradative process proceeds.
mesh_terms: D000818:Animals; D001482:Base Composition; D003080:Cold Temperature; D004277:DNA, Single-Stranded / Q000378:metabolism*; D004720:Endonucleases / Q000378:metabolism; D006358:Hot Temperature; D006868:Hydrolysis; D066298:In Vitro Techniques; D007511:Ischemia / Q000378:metabolism*; D007668:Kidney / Q000098:blood supply*; D008297:Male; D051379:Mice; D015719:Single-Strand Specific DNA and RNA Endonucleases; D013997:Time Factors
chemical_list: D004277:DNA, Single-Stranded; D004720:Endonucleases; D015719:Single-Strand Specific DNA and RNA Endonucleases