Isoform 1 is involved as a ribosomal RNA processing factor in ribosome biogenesis. Binds to tightly bent AT-rich stretches of double-stranded DNA.
Isoform 2 binds to double-stranded DNA.
Subcellular locations: Nucleus, Nucleolus, Cytoplasm, Cytoskeleton, Spindle, Cytoplasm
Colocalizes in the nucleolus during interphase and on the spindle apparatus during mitosis with NPM1.
Subcellular locations: Mitochondrion, Mitochondrion matrix
Imported in a time- and membrane potential-dependent manner to the mitochondrial matrix, but without concomitant processing of the protein. Directed to mitochondria by a novel N-terminal domain that functions as a non-cleavable mitochondrial targeting peptide.
Isoform 2 is much more stable than isoform 1 (at protein level). Ubiquitous. Isoform 1 and isoform 2 are expressed in kidney, liver, blood vessel, brain, mammary gland, skeletal muscle, small intestine and submandibularis. Isoform 1 transcripts are much more abundant than isoform 2 in each tissue analyzed.