Fig. 6.

Uncleavable hnRNP A1 rescues splicing and inhibits cell death. (A–C) HeLa cells stably expressing WT or GzmA-uncleavable mutant HA-hnRNP A1 were treated with PFN plus GzmA or GzmB. Death was monitored by a 4-h ⁵¹Cr release assay (A) and annexin V/propidium iodide staining 1 h later for flow cytometry (B). Data in A show mean ± SD of three independent experiments of percent specific lysis after subtraction of percent specific lysis of control cells treated with PFN alone. Data in B show mean ± SEM of pooled data from six independent experiments. (C) RNA isolated from whole cells 1 h after treatment was analyzed by qRT-PCR to compare spliced/unspliced total cellular RNA. The ratio was normalized to untreated cells. Data are mean ± SEM of five independent experiments. In all panels, statistical differences between WT and mutant hnRNP A1-expressing cells were calculated using a paired Student’s t test.