Altered binding of mutated presenilin with cytoskeleton‐interacting proteins

[摘要]

The majority of familial Alzheimer's disease (AD) cases are linked to mutations on presenilin 1 and 2 genes (PS1 and PS2). The normal function of the proteins and the mechanisms underlying early-onset AD are currently unknown. To address this, we screened an expression library for proteins that bind differentially to the wild-type PS1 and mutant in the large cytoplasmic loop (PS1L). Thus we isolated the C-terminal tail of the 170 kDa cytoplasmic linker protein (CLIP-170) and Reed–Sternberg cells of Hodgkin's disease-expressed intermediate filament-associated protein (Restin), cytoplasmic proteins linking vesicles to the cytoskeleton. PS1L binding to CLIP-170/restin requires Ca²⁺. Treating cells with thapsigargin or ionomycin increased the mutated PS1 in CLIP-170 immunoprecipitates. Further, PS1 and CLIP-170 co-localize in transfected cells and neuronal cultures.

[学科分类] 生物化学/生物物理

[关键词] Alzheimer's disease;Presenilin;Mutation;170 kDa cytoplasmic linker protein;Restin;Protein interaction;aa;amino acid;AD;Alzheimer's disease;APP;amyloid precursor protein;AT;PS1 N-terminus-directed antibodies;β-Gal;β-galactosidase;BSA;bovine serum albumin;CLIP-170;170 kDa cytoplasmic linker protein;CT;PS1 C-terminus-directed antibodies;DMEM;Dulbecco's modified essential medium;EDTA;ethanyldiamino tetraacidic acid;ER;endoplasmic reticulum;FAD;familial Alzheimer's disease;FCS;fetal calf serum;GST;glutathione-S-transferase;IPTG;isopropyl β-D-thiogalactopyranoside;K d;dissociation constant;MIP;microtubule-interacting protein;MNR2;peptide corresponding to 311–330 amino acids of PS1;nt;nucleotide;PBS;phosphate-buffered saline;PS1;presenilin 1;PS2;presenilin 2;Restin;Reed–Sternberg cells of Hodgkin's disease-expressed intermediate filament-associated protein;SREBP;sterol regulatory binding protein;TBS;Tris-buffered saline;wt;wild-type;Zeo;zeocin resistance gene