RADIATION-INDUCED FREE POLYDEOXYRIBONUCLEOTIDES IN LYMPHOID TISSUES: A PRODUCT OF THE ACTION OF DEOXYRIBONUCLEASE I,
Abstract
Physico-chemical studies on the saline-extractable polydeoxyribonucleotides (PDN) occurring in lymphoid tissues 4 hours after whole-body exposure to 600 rads X-irradiation revealed the following information: (1) Viscosity, precipitability by acids and alcohols, and behavior on gel-filtration columns suggest a molecular weight less than that of undegraded DNA but probably greater than 100000. (2) Thermal transition curves indicate extensive complementary double stranding with slight 'fraying' of the ends of the strands. (3) In 0.2 M NaCl, PDN has a lower affinity for histone than does DNA. (4) Susceptibility of PDN to the action of venom phosphodiesterase (EC 3.1.4.1) and resistance to spleen phosphodiesterase (EC 3.1.4.1) demonstrate the presence of 3'-hydroxyl terminals and the absence of 5'-hydroxyl terminals. (5) The above observations suggest that PDN was formed from DNA by the action of a deoxyribonuclease I-like (EC 3.1.4.5) endonuclease rather than a deoxyribonuclease II-like (EC 3.1.5.6) endonuclease in the irradiated tissue. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Mar 01, 1966
- Accession Number
- AD0631144
Entities
People
- K. F. Swingle
- Leonard J. Cole
Organizations
- Naval Radiological Defense Laboratory