Cell division cycle and apoptosis regulator protein 1is aproteinthat in humans is encoded by theCCAR1gene. The deduced 1,150-amino acid CARP1 protein contains a putative cold-shock protein domain expected to bind RNA and a putative DNA-binding motif predicted to be involved in chromosomal organization. Immunohistochemical analysis detected CARP1 in the perinuclear compartment of human breast cancer cells, and the protein had an apparent molecular mass of 130 kD by SDS-PAGE.