Poly(ADP-ribose) polymerase 2 (PARP-2) is a newly discovered member of the PARP 
family. We report the association of PARP-2 with mammalian centromeres in a 
cell-cycle-dependent manner, accumulating at centromeres during prometaphase and 
metaphase, disassociating during anaphase, and disappearing from the centromeres 
by telophase. Analysis of a pseudodicentric chromosome and a human neocentromere 
indicates that PARP-2 binding occurs only at active centromeres in a 
sequence-independent manner. Centromere binding peaks at the outer centromere 
region, and is significantly enhanced upon treatment with microtubule-inhibiting 
drugs. Co-immunoprecipitation assay demonstrates interaction between PARP-2 and 
its functional homolog PARP-1, constitutive centromere proteins Cenpa and Cenpb, 
and spindle checkpoint protein Bub3, but not with a third constitutive 
centromere protein Cenpc. These results, together with our previous 
demonstration that PARP-1 displays an identical binding pattern with Cenpa, 
Cenpb and Bub3, but not Cenpc, and that all three proteins undergo significant 
poly(ADP-ribosyl)ation upon gamma-irradiation of cells, point to possible 
diverse roles of PARP-2 and PARP-1 in modulating the structure and checkpoint 
functions of the mammalian centromere, in particular during radiation-induced 
DNA damage.