Moderately suppressed migration of HSCs in the absence of ATF4. (A) Cell number per FL at E11.5 (n = 4 for each group). (B-C) Donor chimerism and RU of E11.5 FL cells at 12 weeks after transplantation (n = 8 for each group). (D) Transwell assay of 104 LSK cells in the ATF4+/+ or ATF4−/− FL. Cell counts in the lower chamber are shown (n ≥ 9 for each group; 3 independent experiments). Student t test *P < .05, **P < .01, and ***P < .001.