DNA fragmentation into 200–250 and/or 30–50 kilobase pair fragments in rat liver nuclei is stimulated by Mg2+ alone and Ca2+/Mg2+ but not by Ca2+ alone

FEBS Letters

Inayat-Hussain, Salmaan H.¹  Wolfe, James T.¹  Cain, Kelvin¹  Cohen, Gerald M.¹ 

[1] MRC Toxicology Unit, Hodgkin Building, University of Leicester, PO Box 138, Lancaster Rd, Leicester LE1 9HN, UK

关键词: Apoptosis;    DNA fragmentation;    Magnesium;    Endonuclease;   

DOI  :  10.1016/0014-5793(94)80001-4

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Internucleosomal cleavage of DNA has often been regarded as the biochemical hallmark of apoptosis. We now demonstrate in isolated rat liver nuclei that DNA is initially cleaved into ⩾700, 200–250 kbp and 30–50 kbp fragments via a multi-step process, which is activated by Mg⁺ and Mg²⁺+Ca²⁺ but not by Ca²⁺ alone. The subsequent internucleosomal cleavage requires both cations. These findings demonstrate that a key event in the apoptotic process is the fragmentation of DNA into large kbp fragments by either a Mg²⁺ -dependent process (which can be potentiated by Ca²⁺) and/or by a Ca²⁺/Mg²⁺ activated endonuclease(s).

【 授权许可】

Unknown