TY - JOUR
T1 - Presenilin-2 mutations modulate amplitude and kinetics of inositol 1,4,5-trisphosphate-mediated calcium signals
AU - Leissring, Malcolm A.
AU - Parker, Ian
AU - LaFerla, Frank M.
PY - 1999/11/12
Y1 - 1999/11/12
N2 - Mutations in the two presenilin genes (PS1, PS2) account for the majority of early-onset familial Alzheimer's disease (FAD) cases. Converging evidence from a variety of experimental systems, including fibroblasts from FAD patients and transgenic animals, indicates that PS1 mutations modulate intracellular calcium signaling pathways. Despite the potential relevance of these changes to the pathogenesis of FAD, a comparable effect for PS2 has not yet been demonstrated experimentally. We examined the effects of wild-type PS2, and both of the identified FAD mutations in PS2, on intracellular calcium signaling in Xenopus oocytes. Inositol 1,4,5-trisphosphate (IP3)- evoked calcium signals were significantly potentiated in cells expressing either of the PS2 mutations relative to wild-type PS2-expressing cells and controls. Decay rates of calcium signals were also significantly accelerated in mutant PS2-expressing cells in a manner dependent upon IP3 concentration. The finding that mutations in both PS1 and PS2 modulate intracellular calcium signaling suggests that these disturbances may represent a common pathogenic mechanism of presenilin-associated FAD.
AB - Mutations in the two presenilin genes (PS1, PS2) account for the majority of early-onset familial Alzheimer's disease (FAD) cases. Converging evidence from a variety of experimental systems, including fibroblasts from FAD patients and transgenic animals, indicates that PS1 mutations modulate intracellular calcium signaling pathways. Despite the potential relevance of these changes to the pathogenesis of FAD, a comparable effect for PS2 has not yet been demonstrated experimentally. We examined the effects of wild-type PS2, and both of the identified FAD mutations in PS2, on intracellular calcium signaling in Xenopus oocytes. Inositol 1,4,5-trisphosphate (IP3)- evoked calcium signals were significantly potentiated in cells expressing either of the PS2 mutations relative to wild-type PS2-expressing cells and controls. Decay rates of calcium signals were also significantly accelerated in mutant PS2-expressing cells in a manner dependent upon IP3 concentration. The finding that mutations in both PS1 and PS2 modulate intracellular calcium signaling suggests that these disturbances may represent a common pathogenic mechanism of presenilin-associated FAD.
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U2 - 10.1074/jbc.274.46.32535
DO - 10.1074/jbc.274.46.32535
M3 - Article
C2 - 10551803
AN - SCOPUS:0032704888
SN - 0021-9258
VL - 274
SP - 32535
EP - 32538
JO - Journal of Biological Chemistry
JF - Journal of Biological Chemistry
IS - 46
ER -