Fig. 3: TRIM26 regulates GSC self-renewal via its C-terminal PRYSPRY domain.

A GSCs were transduced with TRIM26 RNAi or control and subjected to the extreme limiting dilution assay (ELDA). Data represent mean ±  SEM (n = 3, ANOVA, ***P < 0.005). See Source Data File for exact P values and statistical parameters. B GSCs treated as in (A) were subjected to ELDA. Data represent mean ±  SEM (n = 5, ANOVA, ***P < 0.0001). See Source Data File for exact P values and statistical parameters. C GSCs transduced with TRIM26 RNAi or control were transduced 2 days later with SOX2-expressing or vector (Vec) lentiviruses and subjected to ELDA. Data represent mean ±  SEM (n = 3, ANOVA, *P < 0.05, ***P < 0.0005). See Source Data File for exact P values and statistical parameters. D In vitro translated, ³⁵S-labeled full-length (FL) TRIM26 and domain deletion mutants were used in GST pulldown assays using glutathione beads and bacterially produced GST control or GST-SOX2 (*FL SOX2). TRIM26 proteins were visualized by gel electrophoresis and fluorography (middle panel: input). GST-fusion proteins were visualized by Coomassie brilliant blue (CBB) staining. Data were representative of three independent experiments. E In vitro translated, ³⁵S-labeled full-length (FL) TRIM26, TRIM26 1-363, and TRIM26 PRYSPRY domain were used in GST pulldown assays with GST control or GST-SOX2 as in (D). Data were representative of three independent experiments. F GSCs transduced with TRIM26 RNAi or control were treated 2 days later with either vector or TRIM26 GFP-PRYSPRY-expressing lentiviruses. Four days later, lysates were subjected to immunoblotting. Data were representative of three independent experiments. G GSCs transduced with TRIM26 RNAi or control were transduced 2 days later with either vector (Vec) or TRIM26 GFP-PRYSPRY-expressing lentiviruses and then subjected to ELDA as in (A). Data represent mean ±  SEM (n = 5, ANOVA, **P < 0.01, ns nonsignificant). See Source Data File for exact P values and statistical parameters.