Quercetin and Quercetin-Rich Red Onion Extract Alter Pgc-1α Promoter Methylation and Splice Variant Expression

Figure 2

(a) Schematic structures of the 5′ and 3′ regions of Pgc-1α are shown for each isoform. The 5′ schematic was slightly adapted from Miura et al. 2008. The proximal (exon 1a) or alternate (exon 1b) promoters can be spliced to exon 2. Within exon 1b, upstream (exon 1b) or downstream (exon 1b′) splicing to exon 2 can occur. Splicing also occurs between exons 6 and 7 near the 3′ end of the gene. Exon 6 can be spliced directly to exon 7, at two separate regions, 7a or 7b. Alternatively, exon 6 can be spliced to the intronic region preceding exon 7 to result in a truncated form of Pgc-1α. Total NT-Pgc-1α, FL-Pgc-1α, and total Pgc-1α all contain exons 1b:1b′, 1a, and 2 as indicated. Total Pgc-1α contains both exons 6 and 7, as indicated. (b) Schematic representation of the start and stop of each Pgc-1α isoform is shown. Primer pairs have previously been designed and published, and the corresponding reference for each pair is indicated. is the alternative splice site between exons 6 and 7.

(a)

(b)