Figure 6.
Gene expression changes due to Calr haploinsufficiency and the CALRdel52 mutant. (A) Cell collection conditions in RNAseq experiments. Unpurified BM cells (1 × 106; B6-CD45.2) were transplanted into lethally irradiated recipients (B6-CD45.1; n = 9-12 in each group). At 8 to 12 weeks after transplantation, 2 × 104 CD45.2+ LSK cells were sorted from BM cells pooled from 3 recipient mice and used as a sample for RNAseq analysis. We prepared a total of 14 samples: 3 WT, 3 Calr+/−, 4 CALRdel52;Calr+/+, and 4 CALRdel52;Calr+/−. (B) Unsupervised hierarchical clustering of the global gene expression signatures. (C) Venn diagram depicting differentially expressed genes in LSK cells from Calr+/−, CALRdel52;Calr+/+, and CALRdel52;Calr+/− mice relative to WT controls (false discovery rate <0.1). Forty-seven genes were differentially expressed (23 upregulated and 24 downregulated) in Calr+/− mice. (D) Hierarchical clustering of expression profiles of these 14 samples according to the 47 genes differentially expressed in Calr+/− mice. Genes (rows) and genotypes (columns) with dendrograms are shown. Dendrograms were constructed using Pearson correlation. This analysis distinguished the 4 genotypes relatively clearly. The second cluster of genes was upregulated in Calr+/− mice and CALRdel52;Calr+/− mice and was clearly downregulated in WT and CALRdel52;Calr+/+ mice (colored with red). (E) Result of GSEA analysis showing enrichment of the stem cell signature29 in CALRdel52;Calr+/− LSK cells compared with CALRdel52;Calr+/+ LSK cells. (F) GSEA results using hallmark gene sets for CALRdel52;Calr+/− and CALRdel52;Calr+/+ LSK cells. Heatmap shows the normalized enrichment score (NES) of significantly altered gene sets in CALRdel52;Calr+/− cells compared with CALRdel52;Calr+/+ cells (false discovery rate q value <0.25 or normalized P value <.05). Positive ES (red) indicates that the gene set was enriched in CALRdel52;Calr+/− LSK cells, and negative ES (blue) indicates that the gene set was de-enriched in CALRdel52;Calr+/− LSK cells. Result of GSEA analysis gene sets highlighted in blue or red are shown