Panel A: A set of immunoblots showing the expression and phosphorylation of STAT2 and STAT1 proteins in primary fibroblasts. The samples include three healthy controls (HC1, HC2, HC3), two patients (P1, P2), and their mother (I.2). The blots are probed for STAT2, phosphorylated STAT2 (pSTAT2), beta-actin (loading control), STAT1, and phosphorylated STAT1 (pSTAT1). The patients P1 and P2 show absent STAT2 expression, while their mother shows lower expression. Panel B: A set of immunoblots showing the expression and phosphorylation of STAT2 and STAT1 proteins in HEK293T cells transfected with various STAT2 variants. The samples include non-transfected (NT), empty-vector (EV), wild-type (WT), R510X (positive control), K490Qfs 41 (variant in P1 and P2), P3s splice variants: INSin9 (insertion of intron 9), INSin8 (insertion of 47 nucleotides of intron 8), DELex9 (deletion of Exon9). The blots are probed for STAT2, phosphorylated STAT2 (pSTAT2), beta-actin (loading control), STAT1, and phosphorylated STAT1 (pSTAT1). The variants show different levels of STAT2 expression and phosphorylation.
The STAT2 variants impair STAT2 protein expression and phosphorylation. (A and B) Transfected HEK293T cells (B) and primary fibroblasts (A) were stimulated with 10,000 IU/ml IFN-α2A and 1,000 IU/ml IFNγ for 30 min. (A) Immunoblots of whole-cell extracts from primary fibroblasts of P1 and P2, their mother (I.2), and three healthy controls (HC) show an absent STAT2 expression in P1 and P2, as well as a lower expression in their mother (I.2). A representative blot from two experiments is shown. (B) Immunoblots of whole-cell extracts from HEK293T cells transfected with the following STAT2 variants: NT (non-transfected), EV (empty vector), WT (wild-type), R510X (positive control), K490Qfs*41 (variant in P1 and P2), and P3’s splice variants: INSin9, INSin8, and DELex9. A representative blot from three experiments is shown. Source data are available for this figure: SourceData F3.