Decreased expression of RPS14 or RPS19 activates the p53 pathway. (A) Increased levels of total p53 protein in primary human bone marrow cells as analyzed by intracellular flow cytometry. (B) RPS14 shRNAs significantly increase the expression of downstream target genes of p53, as assessed by gene set enrichment analysis using a set of published p53 target genes.16 Genes are ranked according to their differential expression between cells expressing RPS14 shRNA and control shRNAs targeting the luciferase gene. Genes in the p53 gene set are marked with vertical bars, and the enrichment score is shown in green. (C-D) The mRNA expression of p21 and Bax in primary human bone marrow cells, relative to β-actin mRNA, was measured by quantitative real time PCR. (E) Cell cycle status was analyzed by flow cytometry using 7-AAD and BrdU. Numbers in the flow plot represent the percentage of cells in different phases of cell cycle. Results shown for each experiment are representative of 3 independent experiments performed in triplicate (mean ± SEM). *P < .05. **P < .01.
