Nuclear translocation of a leukocyte elastase inhibitor/elastase complex during staurosporine-induced apoptosis: Role in the generation of nuclear L-DNase II activity
Ca. Belmokhtar et al., Nuclear translocation of a leukocyte elastase inhibitor/elastase complex during staurosporine-induced apoptosis: Role in the generation of nuclear L-DNase II activity, EXP CELL RE, 254(1), 2000, pp. 99-109
Using L1210 murine leukemia cells, we have previously shown that in respons
e to treatment with drugs having different targets, apoptotic cell death oc
curs through at least two different signaling pathways. Here, we present ev
idence that nuclear extracts from staurosporine-treated cells elicit DNase
II activity that is not detected in nuclear extracts from cisplatin-treated
cells. This activity correlates with the accumulation of two nuclear prote
ins (70 and 30 kDa) which are detected by an anti-L-DNase II antibody. Part
ial purification of this DNase II activity suggests that the 30-kDa protein
could be the nuclease responsible for staurosporine-induced DNA fragmentat
ion. The 70-kDa protein is also recognized by an anti-elastase antibody, su
ggesting that it carries residues belonging to both L-DNase II and elastase
, Since previous findings showed that L-DNase II was generated from the leu
kocyte inhibitor of elastase, we propose that the 70-kDa protein results fr
om an SDS-stable association between these two proteins and is translocated
from the cytoplasm to the nucleus during staurosporine-induced apoptosis.
(C) 2000 Academic Press.