Pro-apoptotic function of calsenilin/DREAM/KChIP3.

Apoptotic cell death and increased production of amyloid b peptide (Ab) are pathological features of Alzheimer's disease (AD), although the exact contribution of apoptosis to the pathogenesis of the disease remains unclear. Here we describe a novel pro-apoptotic function of calsenilin/DREAM/KChIP3. By antisense oligonucleotide-induced inhibition of calsenilin/DREAM/KChIP3 synthesis, apoptosis induced by Fas, Ca2+-ionophore, or thapsigargin is attenuated. Conversely, calsenilin/DREAM/KChIP3 expression induced the morphological and biochemical features of apoptosis, including cell shrinkage, DNA laddering, and caspase activation. Calsenilin/DREAM/KChIP3-induced apoptosis was suppressed by caspase inhibitor Z-VAD and by Bcl-XL, and was potentiated by increasing cytosolic Ca2+, expression of Swedish amyloid precursor protein mutant (APPSW) or presenilin 2 (PS2), but not by a PS2 deletion lacking its C-terminus (PS2/411stop). In addition, calsenilin/DREAM/KChIP3 expression increased Ab42 production in cells expressing APPsw, which was potentiated by PS2, but not by PS2/411stop, which suggests a role for apoptosis-associated Ab42 production of calsenilin/DREAM/KChIP3.