Figure 3.
Significant differences in translational efficiencies of DNA damage repair pathway genes between patient clusters. (A) Volcano plot showing the results of the Xtail analysis. Genes highlighted in red are those with a fold change of at least 2, and an adjusted P < .05. The final list of 748 changing genes discards genes with low raw read counts (supplemental Table 4; “Materials and methods”). (B) Heat map showing the log2 TE values for the 88 genes listed in Figure 4. (C) The 748 genes that are differentially translated between type A and type B were subjected to a function and pathway enrichment analysis using Qiagen’s Ingenuity Pathway Analysis tool (IPA). Plot shows enriched canonical pathways at adjusted P < .001 (−log(Benjamini-Hochberg P value) shown as blue bars), with ratio (the proportion of the genes in the pathway that are also found in our list) shown as orange line. There are some pathways in this plot that do not appear relevant to the functioning of B lymphocytes. Their presence is explained by the reuse of the same signaling proteins in various pathways in different cell lineages. (D) Western blot analysis of ATM protein expression for 8 samples (10, 18, 25, 27, 28, 29, 30, and 31) subjected to ribosome profiling. No material was available for samples 22 and 24. (E) Normalized ATM levels (ATM fluorescence signal to GAPDH fluorescence signal) is shown for type A and type B patients. Error bars show mean ± SEM. Sample 18 (blue dot) in type A patients, was found to bear an ATM mutation (supplemental Table 1) and was excluded from the statistical analysis. Normalized ATM levels are significantly higher in type A than type B (unpaired 2-tailed Student t test, *P = .02).