2006年7月3日 · Cdc6 is specifically cleaved at two sites by caspase-3 during etoposide-induced apoptosis. In etoposide-induced apoptosis of HeLa cells, the 62-kD Cdc6 protein is specifically cleaved into fragments of 49 and ∼36 kD, with kinetics similar to that of the proteolytic cleavage of poly (ADP-ribose) polymerase (PARP; Fig. 1 A).

2021年8月2日 · In HeLa cells that are characterized by lower repair capacity, UV irradiation caused a reduction of the levels of Cdc6, Orc2 and Orc3, but not of Orc4 or triggered apoptosis. The appearance of the truncated 49 kDa form of Cdc6 suggested the involvement of the caspase pathway in the degradation of the proteins.

We prepared nuclear lysates from HeLa cells and released Cdc6 from chromatin with nuclease. These extracts were subjected to immunoprecipitation with anti-Huwe1 antibodies and then probed for endogenous Cdc6. Cdc6 was found in Huwe1 immunoprecipitates both in the absence and in the presence of DNA damage (Figure 3 G, lanes 5 and 6).

2006年1月27日 · Taken together, our results indicate that depletion of Cdc6 by Cdc6-specific esiRNA causes two distinct abnormalities in HeLa cells, depending on the timing of Cdc6 loss. Depletion of Cdc6 in synchronous G1 cells blocked cells at G1/S transition, consistent with the well-known functions of Cdc6 in origin licensing and replication initiation ...

2009年6月1日 · Our findings reveal that ATR kinase phosphorylates Cdc6 at serine residue 6 in in vitro. In addition, we demonstrate that the total cellular and chromatin-bound levels of Cdc6 increase in an ATR activity-dependent manner and are maintained, during the S-phase arrest of HU-induced HeLa cells.

Here, we demonstrate that ATR (AT mutated and Rad3 related) activity is essential for maintaining high chromatin levels of the Cdc6 protein, thereby delaying entry into mitosis during hydroxyurea (HU)-induced S-phase arrest of HeLa cells.

Pulse-chase experiments show that chromatin-bound newly synthesized Cdc6p has a half life of 2-4 h. The results indicate that, once bound to chromatin, pulse-labeled new Cdc6p behaves just as old Cdc6p: it dissociates and eventually disappears from the nucleus. The data suggest a surprisingly dynamic behaviour of Cdc6p in the HeLa cell cycle.

Reduced protein levels of Cdc6 were detected in UV damaged HeLa cells in which the apoptotic process was blocked with the caspase inhibitor Z-VAD-fmk, indicating that the degradation of Cdc6...

2000年9月9日 · Human CDC6 activity is regulated by periodic transcription and CDK-regulated subcellular localization. Here, we show that, in addition to being absent from nonproliferating cells, CDC6 is targeted for ubiquitin-mediated proteolysis by the anaphase promoting complex (APC)/cyclosome in G 1.

1998年12月15日 · We exploit an improved mammalian cell‐free DNA replication system to analyse quiescence and Cdc6 function. Quiescent 3T3 nuclei cannot initiate replication in S phase cytosol from HeLa or 3T3 cells...