Bhaskar M S, Rao K S
Department of Biochemistry, School of Life Sciences, University of Hyderabad, India.
Biochem Mol Biol Int. 1994 May;33(2):377-84.
Melting temperatures (Tm) of the DNA isolated from young, adult, and old rat brain neurons and astrocytes were recorded under different conditions. There was a rise in Tm and decrease in hyperchromicity in the old when compared to the young and adult. Single and double strand breaks were assessed by using nick translation type incubation of DNA with E. coli Pol I and addition of nucleotides at the terminal 3'-OH by calf thymus terminal deoxynucleotidyl transferase. Results show that DNA from old brain cells is more compact in conformation. However, there is also an increase in the number of single and double strand breaks with age in both neuronal and astroglial DNA.
在不同条件下记录从幼年、成年和老年大鼠脑神经元及星形胶质细胞中分离出的DNA的解链温度（Tm）。与幼年和成年大鼠相比，老年大鼠的Tm升高，增色效应降低。通过使用大肠杆菌Pol I对DNA进行切口平移式孵育，并利用小牛胸腺末端脱氧核苷酸转移酶在3'-OH末端添加核苷酸来评估单链和双链断裂情况。结果表明，老年脑细胞的DNA构象更紧密。然而，神经元和星形胶质细胞DNA中的单链和双链断裂数量也随着年龄增长而增加。
