Figure 1

Position of primers and oligonucleotide probes designed to amplify hypoxia inducible factor 1α ( HIF-1α ) mRNA splice variants. The diagram illustrates the combination of primers and probes used to detect mRNA of four alternative spliced isoforms of HIF-1α. Boxes represent exons designated by 1 to 15. Primers are indicated by solid arrowhead and probe by thick solid lines. Wild-type HIF-1α (HIF-1α ^wt) mRNA consists of 15 exons and 14 introns. Variants reported here are generated by a TAG insertion between exon 1 and exon 2 (HIF-1α ⁸²⁷and HIF-1α ⁷³⁶), exon 13 to 15 alternative splicing (HIF-1α ⁷³⁶), exon 11 to 13 alternative splicing (HIF-1α ⁵⁵⁷) and exon 10 to 13 alternative splicing (HIF-1α ⁵¹⁶). Primers on exons 5 and 6 (asterisk) are suitable for quantification of all HIF-1α transcripts including HIF-1α ^wtas well as each isoform. Primers pairs on exons 13 and 15, 11 and 13, 10 and 13 are suitable for specific detection of HIF-1α ⁷³⁶, HIF-1α ⁵⁵⁷and HIF-1α ⁵¹⁶variants respectively. Note that primers on exons 1 and 2 allow mRNA detection of both isoforms HIF-1α ⁸²⁷and HIF-1α ⁷³⁶.