CEP131 Abrogates CHK1 Inhibitor-Induced Replication Defects and Is Associated with Unfavorable Outcome in Neuroblastoma

Figure 2

Centrosome-associated protein 131 (CEP131) was identified as an MDM2 interacting protein in response to CHK1i (PF-477736). (a) Coomassie staining of anti- MDM2 immunoprecipitates. Whole-cell extracts from NB-39-nu cells treated with 1 μM CHK1i or DMSO (NT) for 24 h were immunoprecipitated (IP) with anti-MDM2 antibody. The densely stained band ranging in molecular weight from 100 to 150 KDa (Red arrow) was recovered and analyzed by mass spectrometry. (b) Mass spectrometric analysis. The listed proteins were shown in descending order of peptide coverage. The red arrow indicates CEP131. (c) Immunoprecipitation analysis with MDM2 and CEP131. NB-39-nu cells were treated with 1 μM CHK1i for 24 h and were coimmunoprecipitated (IP) with mouse control IgG or with anti-MDM2 antibody. The immunocomplexes were resolved and immunoblotted with the indicated antibody. The immunoblots using whole-cell lysates ensured equal loading (INPUT).

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