Fig. 5.

Changes in the expression of splice factors and splice factor kinases in response to hypoxia. a This panel illustrates the presence of potential hypoxia inducible factor (HIF) binding sites in the promoters of six splice factor (SRSF1, SRSF2, SRSF3, SAM68, HuR, hnRNPA1) and two splice factor kinase genes (CLK1, SRPK1), orange boxes. b Quantitative PCR measurement of splice factor and splice factor kinase expression, PC3 cells in normoxia or hypoxia for 48 h. The housekeeping gene was UBC. c Western blot confirming increased levels of CLK1 and its substrate SRSF1 in hypoxia (PC3 cells, 48 h at 1% oxygen). β-actin is the loading control. d Levels of phosphorylated SR proteins measured with the mAb104 antibody that preferentially binds phosphorylated SR proteins