Format

Send to

Choose Destination
J Mol Biol. 2011 Nov 25;414(2):217-30. doi: 10.1016/j.jmb.2011.09.046. Epub 2011 Oct 4.

Functional implications of the conformational switch in AICD peptide upon binding to Grb2-SH2 domain.

Author information

1
Structural Genomics Division, Saha Institute of Nuclear Physics, 1/AF Bidhan Nagar, WB, Kolkata 700 064, India.

Abstract

It has been hypothesized previously that synergistic effect of both amyloid precursor protein intracellular C-terminal domain (AICD) and Aβ aggregation could contribute to Alzheimer's disease pathogenesis. Structural studies of AICD have found no stable globular fold over a broad range of pH. Present work is based on the premises that a conformational switch involving the flipping of C-terminal helix of AICD would be essential for effective binding with the Src homology 2 (SH2) domain of growth factor receptor binding protein-2 (Grb2) and subsequent initiation of Grb2-mediated endo-lysosomal pathway. High-resolution crystal structures of Grb2-SH2 domain bound to AICD peptides reveal a unique mode of binding where the peptides assume a noncanonical conformation that is unlike other structures of AICD peptides bound to protein-tyrosine-binding domains or that of its free state; rather, a flipping of the C-terminal helix of AICD is evident. The involvement of different AICD residues in Grb2-SH2 interaction is further elucidated through fluorescence-based assays. Our results reveal the significance of a specific interaction of the two molecules to optimize the rapid transport of AICD inside endosomal vesicles presumably to reduce the cytotoxic load.

PMID:
22001015
DOI:
10.1016/j.jmb.2011.09.046
[Indexed for MEDLINE]

Supplemental Content

Full text links

Icon for Elsevier Science
Loading ...
Support Center