Figure 3. GCK1 activation upregulates SRSF1 and induces INSR exon 11 inclusion.
(A) MIN6 cells were exposed to DMEM medium without glucose containing DMSO with or without 25 μM GKA50 for 48 hours. Total RNA was extracted and subjected to RT-PCR using primers from exon 10 and 12 of INSR. Tubulin was used as control. (B) Total SRSF1 mRNA levels from cells described in (A) were detected by qRT-PCR using primers from exon 2 and 3.Tubulin was used for normalization. (C) Western blot of lysates from cells described in (A). (D) Total RNA was isolated from mouse islets of control mice (n = 5) or mice overexpressing GCK1 specifically in β-cells (n = 5) and subjected to RT-PCR using primers from exon 10 and 12 of INSR. GAPDH served as an RT-PCR control. (E) Graph showing quantitation of % exon 11 inclusion in (D). (F) Q-RT-PCR of insulin expression in samples described in (D).