B. Robaye et al., APOPTOTIC CELL-DEATH ANALYZED AT THE MOLECULAR-LEVEL BY 2-DIMENSIONALGEL-ELECTROPHORESIS, Electrophoresis, 15(3-4), 1994, pp. 503-510
The pattern of protein expression and phosphorylation after an apoptot
ic stimulus has been studied in two systems. Bovine aortic endothelial
cells were induced to undergo apoptotic cell death by a combination o
f a cytokine (tumor necrosis factor, TNF) and inhibitors of protein sy
nthesis, like cycloheximide. Two-dimensional (2-DE) electrophoresis of
proteins from such cells revealed specific proteolysis of distinct pr
oteins, some at an early stage of apoptosis and some at a later stage.
These proteins may have antiapoptotic properties. In rat IPC-81 promy
elocytic leukemia cells, cAMP induced apoptosis. 2-DE of such eels pul
se-labeled with [S-35]methionine revealed two ''novel'' protein spots
(of 30 kDa and 46 kDa, respectively), induced very rapidly by a posttr
anscriptional mechanism. It is proposed that '''dysphosphorylation'' m
ay accompany apoptosis in general, since both endothelial cells treate
d with TNF/cycloheximide and IPC-81 cells treated with cAMP analog or
the apoptosis-inducing phosphatase inhibitors okadaic acid or calyculi
n A all showed altered protein phosphorylation patterns, as revealed b
y 2-DE electrophoresis of proteins from cells relabeled with (32)pi.