Dpy30 KO results in loss of HSC identity and down-regulation of key genes for HSC maintenance and function. (A–C) Gene expression analyses of donor-derived LT-HSCs in BM chimeras 2 wk after pIpC injections following the schemes in Fig. 4 A and Fig. S1. (A) GSEA for genes affected in the Dpy30 KO (F/–) HSCs in the BM chimeras, after RNA-seq analyses. The top panel shows an enrichment of LT-HSC (LSK CD48⁻CD150⁺) gene set in genes down-regulated, whereas the bottom panel shows an enrichment of RLP and ST-HSC (LSK CD48⁺) gene set in genes up-regulated, in Dpy30 KO HSCs. Both gene sets are from (He et al., 2011). (B) Relative expression of key HSC-regulatory genes in the control (F/+) versus Dpy30 KO (F/–) HSCs in the BM chimeras, as analyzed by RNA-seq in two independent BM transplantations (TP1 and TP2). (C) Relative expression of the same genes as in B, as analyzed by RT-qPCR and normalized to Actb using HSCs from three independent BM transplantations and shown as mean ± SD. ND, not done due to insufficient RNAs. P < 0.05 for all genes by Student’s t test, except for c-Myc. (D) Western blotting for indicated proteins in whole BMs from pIpC-injected Mx1-Cre; Dpy30^F/+ and Mx1-Cre; Dpy30^F/– mice. (E) A model illustrating HSC regulation by Dpy30 via multiple genes and pathways.