Centrosome number is controlled by a centrosome-intrinsic block to reduplication

摘要: The centrosome duplicates once in S phase. To determine whether there is a block reduplication, we used cell fusion assay to compare the duplication potential of unduplicated G1 centrosomes and recently duplicated G2 centrosomes. By fusing cells different cycle stages, found that were unable reduplicate cellular environment supports duplication. Furthermore, cytoplasm did not inhibit fused cells, indicating reduplication intrinsic rather than cytoplasm. test underlying mechanism, created mononucleate with two by enucleated cytoplasts. Both duplicated, controlled centrosome:nucleus ratio. We also human primary have tight control over number during prolonged S-phase arrest this partially abrogated transformed cells. This suggests link between maintenance genomic stability.