Figure 4.

NO signals induce enhanced ubiquitination of PTEN, leading to protein degradation. (A) Treatments with SNOC, glutamate or Aβ peptides increase PTEN ubiquitination, as determined by IP-Western analysis. (B) Enhanced physical interaction between PTEN and NEDD4-1 upon various treatments at the conditions used in other experiments, as determined by co-immunoprecipitation/Western blot analysis. Figure is chosen as the representative of three independent experiments. (C) Downregulation of NEDD4-1 by siRNA ( 4 μg) prevents PTEN protein degradation upon SNOC treatment.