Skip to main content
. 2022 Feb 15;9(12):2105222. doi: 10.1002/advs.202105222

Figure 5.

Figure 5

Lipid droplets promote Numb degradation by ubiquitination and activate Notch pathway in CRC cells. A,B) Western blot (A) and RT‐qPCR (B) showing Numb and NICD levels in the control and F. nucleatum‐infected HCT116 and HT29 cells. Triacsin C (3 µm) was used to inhibit lipid droplet accumulation. Error bars denote the s.d. (n = 3 per group). p‐Value was calculated using one‐way ANOVA with post‐hoc test. C) Western blot showing Numb and NICD levels in the control and F. nucleatum‐infected HCT116 and HT29 cells. MG‐132 (10 µm) was used to inhibit ubiquitination‐mediated protein degradation. D,E) Fluorescent staining (3D‐SIM) showing F. nucleatum‐elevated Numb (D) and MDM2 (E) localization on lipid droplets. Lipid droplets were visualized by Nile red staining. Scale bar, 5 µm. F) Immunoprecipitation and Western blot showing MDM2‐mediated Numb ubiquitination on the lipid droplets. Lipid droplets were purified from an equal number of control and F. nucleatum‐infected HCT116 and HT29 cells, followed by immunoprecipitation of Numb and Western blotting for Ubiquitin (Ub). AMG‐232 (4 µm) was used to inhibit MDM2 activity. ADRP and GAPDH were used as markers of lipid droplets and cytosolic fraction, respectively.