Stability of spatial interactions between chromocenters and pre-kinetochores in the interphase murine cells

It is known that in mice the centromeric heterochromatin remains compact during the whole cell cycle and at interphase is referred to as "chromocentres". In the current study, by the use of antibodies against prekinetochores and DNA polymerase (a PCNA antigen), we showed that in murine L929 cells chromocentres remain spatially associated with prekinetochores during the entire interphase, including the late S-period, when DNA chromocentres replicate. Augmentation of prekinetochore fluorescence increases concomitantly with the heterochromation replication, but the prekinetochore duplication occurs only in G2 period. A conclusion has been made that murine interphase cells can be used for biochemical fractionation of chromocentres associated with prekinetochore proteins.