As shown in Figure 3C, PS externalization by Ca2+-activated scramblase activity proceeded at identical rates in primary thymocytes from wildtype and ABCA1−/− mice, indicating that human and murine lymphoid cells behave identically in this respect.
The parameters evaluated in vitro were mitochondrial membrane depolarization, phosphatidylserine externalization, caspase 3 activation, DNA fragmentation, and clonogenic activity.
We herein demonstrated that P2Et fraction activity induces apoptosis with MMP loss, PS externalization, caspase 3 activation, and DNA fragmentation.
The inability of ABCA1 knockout mice (ABCA1−/−) to load cholesterol and phospholipids onto apoA1 led to a proposal that ABCA1 mediates the transbilayer externalization of phospholipids, an activity integral not only to the formation of HDL particles but also to another, distinct process: the recognition and clearance of apoptotic cells by macrophages.
The synergistic induction of cell death in IHH was paralleled by increased caspase 3 activity (DEVDase activity) and phosphatidyl serine externalization.
In case of Chromohalobacter salexigens (K30) extract, in spite of a 50-fold increase in caspase-3/7 activity and PS externalization, K-30 neither caused any change in MMP nor cleavage of PARP-1, although a slight increase in γH2Ax was observed indicating DNA damage.
A potential positive effect of ABCA1 activity was suggested by reports that introduction of ABCA1 into HeLa cells specifically activated spontaneous externalization of previously internalized NBD-PS [52] In the higher resolution experiments described here with an independent line of ABCA1-transfected HeLa cells, no difference in externalization was observed.
The learner's package structure is the product of externalization with a series of these activities.
Calcium signaling is therefore expected to control the PI-PLC activity and also the externalization of contactins as clearly demonstrated for the F3/contactin member (Pierre et al., 2001).
In apoptosis, the calcium-dependent phospholipid scramblase activity is activated which results in the externalization of the phosphatidylserine layer of the cell membrane [ 14].
