Sox2 interacts with Grg proteins. (A) subcellular localization of overexpressed MYC-tagged Grg3 or Grg5 in COS-7 cells; immunostaining with anti-Sox2 or anti-MYC antibody. Nuclei were stained with DAPI. (B) Co-transfection of Sox2 with either Grg3 or Grg5, caused the subcellular distribution of the Grgs (red) to alter to reflect that of Sox2 (green). (C) Quantification of cytoplasmic Grg5 using Image J software shows effect of Sox2 on Grg5 subcellular distribution was highly significant (p = 0.0023). (D) Immunoprecipitation of overexpressed MYC-tagged Grg3 or Grg5 in human neural stem cells, after treatment with DPS crosslinker, resulted in co-precipitation of endogenous Sox2. Left hand blot was probed for the Grgs using anti-MYC, right hand panel probed for Sox2 using annti-Sox2 antibody. WCE - whole cell extract. Size markers in lanes 3 and 9, sizes shown to right of image. Scale bar in for panel A and B approximately 10 μm.