PRMT1 promotes mitosis of cancer cells through arginine methylation of INCENP.

Inner centromere protein (INCENP) is a part of a protein complex known as the chromosomal passenger complex (CPC) that is essential for correcting non-bipolar chromosome attachments and for cytokinesis. We here demonstrate that a protein arginine methyltransferase PRMT1, which are overexpressed in various types of cancer including lung and bladder cancer, methylates arginine 887 in an Aurora Kinase B (AURKB)-binding region of INCENP both in vitro and in vivo. R887-substituted INCENP revealed lower binding-affinity to AURKB than wild-type INCENP in the presence of PRMT1. Knockdown of PRMT1 as well as overexpression of methylation-inactive INCENP attenuated the AURKB activity in cancer cells, and resulted in abnormal chromosomal alignment and segregation. Furthermore, introduction of methylation-inactive INCENP into cancer cells reduced the growth rate, compared with those introduced wild-type INCENP or Mock. Our data unveils a novel mechanism of PRMT1-mediated CPC regulation through methylation of INCENP.