Fig. 4.

PGC-1α is not significantly downregulated in the failing heart. (A-B) The expression of PGC-1α mRNA in PGC-1α-cKO mice. The splice isoforms of PGC-1α are shown in Ensembl (http://useast.ensembl.org/index.html). (A) Schematic representation of splice isoforms of PGC-1α and primer sets for detecting them. PGC-1α 203, canonical full length of PGC-1α, encodes 797 amino acids (aa) of protein. PGC-1α 205, lacking Ex11 to 12, encodes 696 aa of protein. PGC-1α 202 is composed of alternative Ex1 and Ex2 to 4, which encodes 142 aa of protein. (B) Relative copy number of indicated PGC-1α splice isoforms. Relative copy number of PGC-1α 203 in wild type mice under basal conditions is defined as 1. N=6–8. (C) PGC-1α specific signal in heart lysate. Western blot analyses were performed with heart lysate derived from PGC-1α-cKO and from HEK293 cells with exogenous PGC-1α expression. Anti-PGC-1α antibodies used for these analyses were Millipore AB3243, Santa Cruz H-300, and Calbiochem ST1204. SE: Short exposure. (D) Relative signal intensities of the signal at 120 KDa/tubulin shown in right panels. N=4–6. (E-F) The proteins levels of PGC-1α are not significantly downregulated in the TAC model (E) and human failing hearts (F). Donors: Healthy hearts. Recipients: Failing hearts. * p<0.05; ** p<0.01; *** p<0.001 as indicated.