CAMK4 (CaMKIV) entry into the nucleus is facilitated by importin alpha (KPNA2). Importin beta and RAN GTPase are not needed for CAMK4 nuclear import (Kotera et al. 2004). CAMK4 nuclear import requires functional kinase domain of CAMK4 (Lemrow et al. 2004) and ATP, but ATP hydrolysis is not needed (Kotera et al. 2005).