FIG. 1.

Human p110 protein is associated primarily with the singular U6atac snRNP but not the U4atac/U6atac di-snRNP. Immunoprecipitation (IP) from HeLa nuclear extract was done with anti-p110 antibodies (anti-p110 IP lane) or nonimmune antiserum (NIS IP lane). RNA was prepared from the immunoprecipitates and 10% of the input (10% input lane), followed by Northern hybridization analysis with a mixed probe detecting U1, U2, U4, U5, and U6 snRNAs or probes specific for U4atac and U6atac. Since U5 snRNA was more difficult to detect than the other snRNAs, an additional, longer exposure is shown for this snRNA in the upper middle gel. In addition, percent immunoprecipitation efficiencies are listed on the right.