Fig. 4

Investigating inhibitory short peptides that can disrupt SOS1/EPS8/ABI1 tri-complex. Confirming the inhibitory capability of short peptides in vivo. a. we generated a series of synthetic inhibitory short peptides (each with 15 aa and overlapped by 5 aa) according to the poly-proline+PxxDY region of ABI1. After LPA stimulation, inhibitory short peptides were added to SK-OV3 cell lysates for 1 h prior to incubation with GST-ABI1 beads. GST-pulldown was employed to determine the effects of these peptides on ABI1-EPS81 binding. b. A series of synthetic inhibitory short peptides was generated (each is 25-amino acids long and overlapped by 5-amono acids) according to the SH3 region of ABI1. GST-pulldown was employed to determine the effects of these peptides on ABI1-SOS1 binding. c. The TAT-containing inhibitory short peptides or control peptides (10 μM) were added into the cell culture of SK-OV3 and incubate for different times. Then, GST-pulldown assay was performed to test the effects of TAT-containing inhibitory short peptides on ABI1-EPS8 interaction. d. The same experiments as above were performed to test the effects of TAT-containing inhibitory short peptides on ABI1-SOS1 interaction