Association of cytokeratin p39 with DNA in intact Novikoff hepatoma cells.
The relationship between the rat tumor-associated cytokeratin p39 (Mr 39,000) and cellular DNA has been studied in intact cells. Using a DNA-protein crosslinking technique, incubation with cis-dichlorodiammineplatinum, we present evidence for the association of p39 with DNA in intact Novikoff ascites hepatoma cells. The cells were treated with cis-dichlorodiammineplatinum and solubilized in NaDodSO4-containing buffer, and the DNA was pelleted by high-speed centrifugation. By immunotransfer analysis, the cytokeratin was found in the DNA pellet of the crosslinked samples while absent from the controls. This result was further substantiated by CsCl density-gradient centrifugation. Collectively, these results suggest a cytokeratin-DNA association at the filament binding sites on or near the nuclear lamina.
D000818:Animals; D000951:Antigens, Neoplasm / Q000378:metabolism; D002467:Cell Nucleus / Q000648:ultrastructure*; D002945:Cisplatin; D004247:DNA / Q000378:metabolism*; D006657:Histones / Q000378:metabolism; D007381:Intermediate Filament Proteins / Q000378:metabolism*; D007633:Keratins / Q000378:metabolism*; D008114:Liver Neoplasms, Experimental / Q000378:metabolism*; D008970:Molecular Weight; D011485:Protein Binding; D051381:Rats
D000951:Antigens, Neoplasm; D006657:Histones; D007381:Intermediate Filament Proteins; D007633:Keratins; D004247:DNA; D002945:Cisplatin