Fig. 6. Association of 53BP1 with RNA. RNA was extracted from 53BP1 immunoprecipitates (lanes 2 and 4) and from normal rabbit IgG control (lanes 3 and 5), labelled with [³²P]pCp, separated on a 6% denaturing polyacrylamide gel, and auto-radiographed. Total nuclear RNA was labelled and used as a control (lane1). After incubation with HeLa nuclear extracts, immuno-affinity beads were washed in two different buffers. In one set (lanes 2 and 3), 100 mM sodium acetate was used as a salt. In the other set (lanes 4 and 5), 150 mM sodium chloride was used. Several bands were enriched in the 53BP1 precipitates (marked with asterisks). Molecular weight marker (MW) was end-labelled fragments of pBR322 digested with MspI. Sizes are indicated as nucleotide length.