|
SampleTypes |
|
lysates, cells ex vivo, cell culture supernatants, serum, plasma
|
|
Specificity |
|
for the quantitative in vitro determination of cytoplasmic histone-associated DNA fragments (mono- and oligonucleosomes) after induced cell death
|
|
Notes |
|
Two distinct forms of eukaryotic cell death can be classified by morphological and biochemical criteria: necrosis and apoptosis. Necrosis is accompanied by increased ion permeability of the plasma membrane; the cells swell and the plasma membrane ruptures within minutes (osmotic lysis). Apoptosis is characterized by membrane blebbing (zeiosis), condensation of cytoplasm, and the activation of an endogenous endonuclease. This Ca2+- and Mg2+-dependent nuclease cleaves double-stranded DNA at the most accessible internucleosomal linker region, generating mono- and oligonucleosomes. In contrast, the DNA of the nucleosomes is tightly complexed with the core histones H2A, H2B, H3, and H4, and is thus protected from cleavage by the endonuclease. The yielded DNA fragments are discrete multiples of an 180-bp subunit, detected as a “DNA ladder” on agarose gels after extraction and separation of the fragmented DNA. The enrichment of mono- and oligonucleosomes in the cytoplasm of the apoptotic cell is due to the fact that DNA degradation occurs several hours before plasma membrane breakdown.
Only Sweden
|