Abrogation of the presenilin 1/beta-catenin interaction and preservation of the heterodimeric presenilin 1 complex following caspase activation.
J Biol Chem
; 273(51): 33909-14, 1998 Dec 18.
Article
in En
| MEDLINE
| ID: mdl-9852041
ABSTRACT
beta-Catenin has previously been shown to interact with presenilin 1 (PS1) in transfected cells. Here we report that beta-catenin co-immunoprecipitates with the endogenous C-terminal fragment of presenilin 1 (PS1-CTF) but not with the endogenous CTF of presenilin 2 (PS2-CTF) in H4 human neuroglioma cells. During staurosporine (STS)-induced cell death, beta-catenin and PS1-CTF undergo a caspase-mediated cleavage. After 12 h of STS treatment, the beta-catenin.PS1-CTF interaction is abrogated. While PS1-CTF immunoprecipitated with all caspase-cleaved species of beta-catenin, beta-catenin holoprotein did not co-immunoprecipitate with the "alternative" caspase-derived PS1-CTF (PS1-aCTF). Thus, the abrogation of the beta-catenin.PS1-CTF complex was due to caspase cleavage of PS1-CTF. beta-Catenin co-immunoprecipitated with PS1-NTF, but only when PS1-NTF was associated with PS1-CTF. Even though PS1-NTF.CTF complex stability was not altered by caspase cleavage, its ability to bind beta-catenin was abolished. Thus, while the PS1-NTF.CTF complex is preserved after caspase cleavage, it may no longer be fully functional.
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Collection:
01-internacional
Database:
MEDLINE
Main subject:
Trans-Activators
/
Caspases
/
Cytoskeletal Proteins
/
Membrane Proteins
Limits:
Humans
Language:
En
Journal:
J Biol Chem
Year:
1998
Document type:
Article
Affiliation country:
United States