May affect the structure or silencing of chromatin by phosphorylating HP1 gamma/CBX3. Isoform 2 promotes the G1/S transition of the cell cycle via up-regulation of CDK2 activity and phosphorylation of CDKN1B, resulting in enhanced nuclear export and proteasome-dependent degradation of CDKN1B. Isoform 2 also represses CDKN1B transcription by phosphorylating and inactivating the transcription factor FOXO3. Plays a role in signal transduction in blood cells. Contributes to both cell proliferation and survival and thus provides a selective advantage in tumorigenesis.
Specificity
Natural and recombinant Human Serine/threonine-protein kinase pim-1
Binds to RP9. Isoform 2 is isolated as a monomer whereas isoform 1 complexes with other proteins. Isoform 1, but not isoform 2, binds BMX. Isoform 2 interacts with CDKN1B and FOXO3.