(A) Schematic figures denote SHANK1 c.3314del
(p.Gly1105fs) and c.3355G>T (p.Glu1119*) variants and resulting SHANK1
protein truncations. (B) HA-SHANK1 (WT, Gly1105fs, or
Glu1119*), GKAP-myc and Homer1b were
co-transfected in HEK293 cells as indicated in the figures. GKAP-myc and Homer1b
in the immunoprecipitates with HA antibody were analyzed by immunoblotting. (C)
The immunoprecipitated HA-SHANK1 (WT, Gly1105fs, or Glu1119*) beads from HEK293
cells were incubated with cultured rat cortical neuron lysates for pulldown
assays. Endogenous Homer1 binding with the immunoprecipitated HA-SHANK1 was
analyzed by immunoblotting.