CDNA CLONING, EXPRESSION, SUBCELLULAR-LOCALIZATION, AND CHROMOSOMAL ASSIGNMENT OF MAMMALIAN AURORA HOMOLOGS, AURORA-RELATED KINASE (ARK)-1 AND ARK-2

Chromosomal segregation during mitosis as well as meiosis is considere d to be regulated by multiple kinases, but the precise mechanism remai ns largely unknown. A mutation in Drosophila, designated aurora, was i dentified as a responsible gene for a chromosomal segregation defect a nd encodes a putative serine-threonine kinase. Here we have identified mammalian aurora homologues, designated aurora-related kinase (ARK) 1 and ARK2. Kinase domains of murine ARK1 and ARK2 showed 61 and 62% id entity, respectively, to that of aurora at the amino acid levels, resp ectively. Cell cycle analysis revealed that the expression of ARK1 was correlated with G2/M phase, while ARK2 was expressed during S and G2/ M phases. Immunofluorescence analysis demonstrated that ARK2 was mainl y localized to the midbody, while ARK1 has been reported to be localiz ed to the spindle pole during mitosis. Collectively, these results sug gest that these two kinases may have distinct roles with different exp ression timing and subcellular localization during the cell cycle prog ression. Interspecific backcross mapping revealed that Ark1 is located in a distal region of mouse chromosome 2, while Ark2 is located in a central region of mouse chromosome 11. (C) 1998 Academic Press.