AIM-1: a mammalian midbody-associated protein required for cytokinesis

Mitosis is a highly coordinated process that assures the fidelity of chromosome segregation, Errors in this process result in aneuploidy which can lead to cell death or oncogenesis, In this paper we describe a putative mammalian protein kinase, AIM-1 (Aurora and Ipl1-like midbody-associated protein), related to Drosophila Aurora and Saccharomyces cerevisiae Ipl1, both of which are required for chromosome segregation. AIM-1 message and protein accumulate at G(2)/M phase, The protein localizes at the equator of central spindles during late anaphase and at the midbody during telophase and cytokinesis, Overexpression of kinase-inactive AIM-1 disrupts cleavage furrow formation without affecting nuclear division, Furthermore, cytokinesis frequently fails, resulting in cell polyploidy and subsequent cell death, These results strongly suggest that AIM-1 is required for proper progression of cytokinesis in mammalian cells.