Figure 5.

Overexpression of PKM2 does not affect HIF-1 activity in intervertebral disc cells, but does so in chondrocytes. A) WT, kinase-dead (K367M), and dimeric mutant (R399E) PKM2 constructs used in panels B–E. B, C) HIF-1 activity in rat NP cells after overexpression of WT (B) or mutant (C) PKM2 did not change. D) HIF-1 activity in AF cells remained unaffected after overexpression of WT or mutant PKM2. E) HIF-1 activity in chondrocytes after overexpression of WT or mutant PKM2 shows increase in NX and at 5% O₂, only with the R399E mutant. Hypoxic culture for all experiments was 24 h. Data are means ± sem of 3 independent experiments, performed with 3 technical replicates per experiment. *P < 0.05.