Skip to main content
. 2020 Aug 18;11:871. doi: 10.3389/fgene.2020.00871

Figure 2.

Figure 2

HIF-1α dynamics under different hypoxic conditions. (A) Bifurcation diagrams of [HIF-1αtot] vs. O2%, in the default parameters setting. The stable and unstable steady states are indicated by solid and dashed lines, respectively. The saddle-node bifurcation points are marked with S1 and S2, while the Hopf bifurcation points are labeled with H1 and H2. (B) Time courses of [HIF-1αtot] for 3% (blue), 1% (red), 0.05% (green), and 0% O2 (orange). The initial values of all the species are set to be their steady states at 21% O2 in the simulation of the dynamics of the species (the same below). (C) Time courses of [HIF-1α] (solid) and [HIF-1α-aOH] (dashed) in moderate hypoxia (1.2% O2) or severe hypoxia (0.04% O2). (D) Bifurcation diagrams of [HIF-1αtot] vs. O2 level for kdhiffih=0.0032 (black) or 0 (red). Notably, kdhiffih is designated as FIH-1-related degration rate of HIF-1α. The types of bifurcation points are similar to Figure 2B.