FIG. 7.
An ETR-3 isoform switch that correlates with cTNT splicing is conserved in avian and mammalian heart development. (A) ETR-3 Western blot of total protein samples extracted from embryonic and adult chicken hearts. Sixty micrograms of total proteins was loaded in each lane. (B) Results from primer extension of endogenous cTNT mRNA from the same time course using a 32P-labeled oligonucleotide complementary to exon 6. (C) ETR-3 Western blot of total protein samples from embryonic-day-14 (e14), newborn (NB), postnatal-day-4 (d4), and adult mouse hearts. Fifty micrograms of total protein was loaded per lane. (D) RT-PCR of endogenous cTNT was performed over the same time course and quantitated by PhosphorImager.