Figure 5.

Sirt1 binding to nucleophosmin (NPM) was required for its inhibitory effect on Nucleolar stress response (NSR). (a) Diagram showing constructs of different Sirt1 deletion mutants. (b) Binding between NPM and deletion mutants of Sirt1. Cells expressing FLAG‐tagged wild‐type or mutant Sirt1 were immunoprecipitated (IP) with anti‐FLAG antibody. Bound NPM was detected by Western blot (WB). (c) Overexpression of Sirt1‐∆265 exhibited no inhibitory effect on ActD‐induced NSR in eGFP‐NPM expressing cells. (d) Co‐expression of Sirt1‐∆519 blunted the inhibitory effect of wild‐type Sirt1 on ActD‐induced NSR in eGFP‐NPM expressing cells. All experiments were performed using HeLa cells. *p < 0.05, one‐way ANOVA, n = 3–4. NS, no significance