PS1 loop shows the strongest FRET with WPE-III-31C-biotin
| Condition | FRET donor FITC labeled | FRET acceptor Cy3 labeled | FITC lifetime (psec) mean ± SD |
|---|---|---|---|
| wt PS1 | PS1 NT (X81) | None | 2630 ± 82 (n = 9) |
| wt PS1 | PS1 loop | WPE-III-31C-biotin | 1815 ± 162* (n = 15) |
| wt PS1 | PS1 NT (X81) | WPE-III-31C-biotin | 2672 ± 44 (n = 14) |
| wt PS1 | PS1 CT | WPE-III-31C-biotin | 2220 ± 110* (n = 12) |
The degree of the fluorescence lifetime shortening indicates that the γ-secretase transition state analog WPE-III-31C is in the closest proximity to the PS1 loop region and far away from PS1 N terminus (n, indicates number of cells). NT, N terminus; CT, C terminus.
↵* p < 0.001 compared with non-FRETing control.