Altered molecular profiles of BM stromal cell subsets in Sipa1^−/−young adult mice. Gene set enrichment analysis was carried out on the RNA-sequencing data to identify differentially expressed genes in the Sipa1^−/− stromal cells. The RNA sequencing was performed on FACS-sorted BM MSCs, MPCs, and endothelial cells from 2 to 3-month-old mice. Data were from 3 independent experiments. False discovery rate-q value represents the false discovery rate of the P value. (A) Upregulated IL-6/JAK2/STAT3 and TGF-β signaling pathways in the Sipa1^−/− MSCs vs Sipa1^+/+ MSCs. (B) The top 25 altered genes in the Sipa1^−/− MPCs relative to that in the Sipa1^+/+ mice. The red frame highlights Thpo gene. Red indicates high expression, and blue indicates low expression. (C) Enhanced TGF-β and TNF-α signaling in the Sipa1^−/− endothelial cells. (D) qPCR analysis of Kitl, Angptl1, Cxcl12, and Runx2 expressions in Sipa1^+/+ and Sipa1^−/− MSCs. (E) qPCR analysis of Kitl, Angptl1, Il7, Cxcl12, Dicer1, and Runx2 expressions in Sipa1^+/+ and Sipa1^−/− MPCs. (F) qPCR analysis of Kitl and Cxcl12 expressions in Sipa1^+/+ and Sipa1^−/− endothelial cells. The statistical differences in panels D-F were analyzed by unpaired Mann-Whitney U test or Kolmogorov-Smirnov test. (G) RNA sequencing revealed upregulation of Epo and Epor in the Sipa1^−/− endothelial cells. P values were calculated by unpaired Student t test. See also in supplemental Figures 5 and 6.