Fig. 5: IκBα KO (LT)- HSC are slow-cycling/dormant and can be mobilized by RARα inhibition.

A Heatmap showing the scaled expression levels of dormancy-associated genes (Cabeza-Wallscheid, 2017) from IκBα WT/Het and KO E14.5 LT-HSCs RNA-seq samples. B Bar chart with the frequencies of BrdU+ E14.5 LT-HSC after 2 h. in vivo labeling with BrdU in E13.5 IκBα WT (n = 6) or KO (n = 4) obtained from n = 10 embryos in 2 independent experiments. Statistical test: unpaired one-tailed t-test with Welch correction (**p-value < 0.01). Bars indicate mean values and error bars refer to ± standard deviation. C Bar chart with percent of Ki67+ cells in indicated cell populations of E14.5 IκBα WT (n = 7) or KO (n = 3). MPP =  multipotent progenitors, ST = Short-term HSCs. n = 7 embryos. Statistical test: unpaired one-tailed Mann–Whitney U-test (*p-value < 0.05, ns p-value > 0.05). Bars indicate mean values, and error bars refer to ± standard deviation. D Bar chart with the percent of BrdU+ cells within the E14.5 FL LT-HSC after in vivo labeling of E10.5 IκBα WT (n = 5) or KO (n = 4) embryos. Statistical test: unpaired one-tailed t-test with Welch correction (*p-value < 0.05). Bars indicate mean values, and error bars refer to ± standard deviation. E Bar chart with the percentage of LT-HSC in G0 phase of the cell cycle after 48 h of ex vivo culture of E14.5 IκBα WT (n = 7) or KO (n = 3) FL lin- cells treated with 10 uM of Ro-41 or DMSO. Data originates from 2 independent experiments with 10 embryos. Statistical test: paired one-tailed t-test for Ro-41 against DMSO comparisons and unpaired one-tailed t-test with Welch correction for WT against KO, in DMSO, comparison (**p-value < 0.01). The horizontal lines indicate mean values and error bars refer to ± standard deviation. Source data are provided as a Source Data file. B, D, E were created with BioRender.com released under a Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International license.