Figure 1. The KRLR sequence plays a role in SALL4 nuclear localization. A “K to R” substitution at position 64 (K64R) results in impaired SALL4 translocation into the nucleus. This remains true for SALL4B mutants with large truncation of lysine-rich domains.⁷ Our sequence alignment confirms that the KRLR sequence is also found in SALL4A. Charged residue, blue; hydrophobic, red.